AO Smith Water Heater Dve 5280120 User Manual

Instruction Manual  
coMMercIal electrIc water heaters  
Models dre-52/80/120 serIes 100  
& dVe-52/80/120 serIes 100  
InstallatIon - operatIon - serVIce  
- MaIntenance - lIMIted warranty  
500 Tennessee Waltz Parkway  
Ashland City, TN 37015  
asMe  
(optIonal)  
Thank you for buying this energy efficient water heater.  
We appreciate your confidence in our products.  
place these InstructIons adjacent to heater and notIfy owner to keep for future reference.  
PRINTED IN THE U.S.A 0908  
196674-002  
safe InstallatIon, use, and serVIce  
the proper installation, use and servicing of this water heater is extremely important to your safety and the safety of others.  
Many safety-related messages and instructions have been provided in this manual and on your own water heater to warn you and  
others of a potential injury hazard. read and obey all safety messages and instructions throughout this manual. It is very important  
that the meaning of each safety message is understood by you and others who install, use, or service this water heater.  
this is the safety alert symbol. It is used to alert you  
to potential personal injury hazards. obey all safety  
messages that follow this symbol to avoid possible  
injury or death.  
danGerindicatesanimminentlyhazardous  
situation which, if not avoided, could result  
in death or injury.  
danGer  
warnInG indicates a potentially hazardous  
situation which, if not avoided, could result  
in death or injury.  
warnInG  
cautIon indicates a potentially hazardous  
situation which, if not avoided, may result  
in minor or moderate injury.  
cautIon  
cautIon used without the safety alert  
symbol indicates a potentially hazardous  
situation which, if not avoided, could result  
cautIon  
in property damage.  
all safety messages will generally tell you about the type of hazard, what can happen if you do not follow the safety message, and  
how to avoid the risk of injury.  
the california safe drinking water and toxic enforcement act requires the Governor of california to publish a list of substances  
known to the state of california to cause cancer, birth defects, or other reproductive harm, and requires businesses to warn of  
potential exposure to such substances.  
this product contains a chemical known to the state of california to cause cancer, birth defects, or other reproductive harm. this  
appliance can cause low level exposure to some of the substances listed, including formaldehyde.  
IMportant defInItIons  
Qualified Installer or Service Agency:  
Installation and service of this water heater requires ability equivalent to that of a Qualified Agency (as defined by ANSI below) in the  
field involved. Installation skills such as plumbing, electrical supply are required in addition to electrical testing skills when performing  
service.  
ANSI Z223.1 2006 Sec. 3.3.83:  
“Qualified Agency” - “Any individual, firm, corporation or company that either in person or through a representative is engaged in and is  
responsible for (a) the installation, testing or replacement of gas piping or (b) the connection, installation, testing, repair or servicing of  
appliances and equipment; that is experienced in such work; that is familiar with all precautions required; and that has complied with all  
the requirements of the authority having jurisdiction.”  
2
General safety InforMatIon  
precautIons  
hydroGen Gas (flaMMaBle)  
DO NOT USE THISAPPLIANCE IFANY PART HAS BEEN UNDER  
WATER. Immediately call a qualified service technician to inspect  
the appliance and to replace any part of the control system which  
has been under water.  
If the unit is exposed to the following, do not operate heater until all  
corrective steps have been made by a qualified service agency.  
1. External fire.  
2. Damage.  
3. Firing without water.  
GroundInG InstructIons  
This water heater must be grounded in accordance with the  
National Electrical Code and/or local codes. These must be  
followed in all cases. Failure to ground this water heater properly  
may also cause erratic control system operation on ELECTRONIC  
CONTROL models.  
Hydrogen gas can be produced in a hot water system served by this  
heater that has not been used for a long period of time (generally two  
weeks or more). Hydrogen gas is extremely flammable. To reduce the  
risk of injury under these conditions, it is recommended that the hot water  
faucet be opened for several minutes at the kitchen sink before using any  
electrical appliance connected to the hot water system. If hydrogen is present  
there will probably be an unusual sound such as air escaping through the pipe  
as the water begins to flow. THERE SHOULD BE NO SMOKING OR  
OPEN FLAME NEAR THE FAUCET AT THE TIME IT IS OPEN.  
This water heater must be connected to a grounded metal, permanent  
wiring system; or an equipment grounding conductor must be run with  
the circuit conductors and connected to the equipment grounding  
terminal or lead on the water heater.  
when servicing this unit, verify the power to the unit is turned off prior to opening the control cabinet door.  
3
taBle of contents  
SAFE INSTALLATION, USE AND SERVICE.....................................2  
Thermostat Settings – Electronic Control Models ...................21  
ELECTRONIC CONTROL MODELS OPERATION.........................21  
Control System Features.........................................................21  
Control System Navigation......................................................21  
Desktop Screen..................................................................21-23  
Temperatures Menu............................................................23-24  
Temperature Settings ..............................................................24  
Heater Status Menu.................................................................25  
Economy Mode Setup Menu ..............................................25-26  
Economy Mode Settings.....................................................26-28  
Alarm Output Setup Menu.......................................................29  
Display Settings Menu.............................................................29  
Heater Information Menu....................................................29-30  
Current Fault / Alert Menu .......................................................30  
Fault Occurrence Menu...........................................................30  
Restore Factory Defaults Menu..........................................30-31  
MAINTENANCE ..............................................................................31  
General...............................................................................31-32  
Flushing...................................................................................32  
Sediment Removal ..................................................................32  
Water and Lime Scale Removal ..............................................32  
TROUBLESHOOTING CHECKLIST ...............................................33  
Not Enough or No Water .........................................................33  
Water Heater Makes Strange Sounds.....................................33  
If You Cannot Identify or Correct the Source of Malfunction ............17  
Leakage Checkpoints..............................................................34  
PIPING DIAGRAMS...................................................................35-42  
WARRANTY....................................................................................43  
GENERAL SAFETY INFORMATION.................................................3  
TABLE OF CONTENTS.....................................................................4  
INTRODUCTION...............................................................................4  
Preparing for the New Installation .............................................4  
DIMENSIONS AND CAPACITIES DATA ...........................................5  
APPROVALS.....................................................................................6  
FEATURES AND COMPONENTS .................................................7-8  
LOCATING THE NEW WATER HEATER..........................................9  
INSTALLATION ...............................................................................10  
Required Ability........................................................................10  
General....................................................................................10  
Mixing Valve Usage .................................................................10  
Chemical Vapor Corrosion.......................................................10  
Circulating Pump .....................................................................10  
Insulation Blankets ..................................................................10  
Temperature-Pressure Relief Valve....................................10-11  
Water Line Connection ............................................................ 11  
Closed Water System.............................................................. 11  
Thermal Expansion.................................................................. 11  
ELECTRICAL ..................................................................................12  
OPERATION....................................................................................19  
General....................................................................................19  
Filling the Water Heater...........................................................19  
Start Up ...................................................................................19  
Draining the Water Heater.......................................................19  
TEMPERATURE REGULATION .....................................................20  
High Temperature Devices ......................................................20  
Thermostat Controls................................................................20  
Thermostat Settings – Surface Mount Control Models............20  
IntroductIon  
Particular attention should be given to the installation of thermometers  
at the locations indicated in the diagrams as these are necessary for  
checking the operation of the heater.  
thank you for purchasing this water heater. Properly installed and  
maintained, it should give you years of trouble free service.  
Abbreviations Found In This Instruction Manual:  
Be sure to turn off power when working on or near the electrical  
system of the heater. never touch electrical components with wet  
hands or when standing in water. When replacing fuses always use  
the correct size for the circuit. see page 13.  
ANSI - American National Standards Institute  
ASME - American Society of Mechanical Engineers  
GAMA - Gas Appliance Manufacturer’s Association  
NEC - National Electrical Code  
NFPA - National Fire Protection Association  
UL - Underwriters Laboratory  
The principal components of the heater are identified on pages 7 & 8.  
The model and rating plate on page 6 interprets certain markings into  
useful information. Both of these references should be used to identify  
the heater, its components and optional equipment.  
preparInG for the InstallatIon  
2. The installation must conform with these instructions and the local  
code authority having jurisdiction and the requirements of the power  
company. In the absence of code requirements, follow NFPA-70  
(current edition). In the absence of local codes, the installation  
must comply with the latest editions of the National Electrical Code,  
NFPA 70 or the Canadian Electrical Code CSA C22.1. The National  
Electrical Code may be ordered from: National Fire Protection  
Association, 1 Batterymarch Park, Quincy, MA02269. The Canadian  
Electrical Code is available from the Canadian StandardsAssociation,  
8501 East Pleasant Valley Road, Cleveland, OH 44131.  
3. If after reading this manual you have any questions or do not  
understand any portion of the instructions, call the toll free number  
listed on the back cover of this manual for technical assistance.  
A sample rating plate is shown on page 6 of this manual. In order  
to expedite your request, please have full model and serial number  
available for the technician.  
1. Read the “General Safety Information” section of this manual first and  
then the entire manual carefully. If you don’t follow the safety rules, the  
waterheatermaynotoperatesafely. ItcouldcauseDEATH, SERIOUS  
BODILY INJURY AND/OR PROPERTY DAMAGE.  
4. Carefully plan your intended placement of the water heater. Examine  
the location to ensure the water heater complies with the “Locating  
the New Water Heater” section in this manual.  
This manual contains instructions for the installation, operation,  
and maintenance of the electric water heater. It also contains  
warnings throughout the manual that you must read and be  
aware of. All warnings and all instructions are essential to the  
proper operation of the water heater and your safety. read  
the entIre Manual Before atteMptInG to Install  
or operate the water heater.  
Installation and service of this water heater requires ability equivalent  
to that of a licensed tradesman or qualified agency (page 2) in the  
field involved. Plumbing and electrical work are required.  
5. For installation in California this water heater must be braced or  
anchored to avoid falling or moving during an earthquake. See  
instructions for correct installation procedures. Instructions may be  
obtained from California Office of the StateArchitect, 1102 Q Street,  
Suite 5100, Sacramento, CA 95811.  
Detailed installation diagrams are in this manual. These diagrams will  
serve to provide the installer with a reference for the materials and  
method of piping suggested. IT IS NECESSARY THAT ALL WATER  
PIPING AND THE ELECTRICAL WIRING BE INSTALLED AND  
CONNECTED AS SHOWN IN THE DIAGRAMS.  
6. Massachusetts Code requires this water heater to be installed in  
accordance with Massachusetts 248-CMR 2.00: State Plumbing Code  
and 248-CMR 5.00.  
4
dIMensIons and capacItIes data  
dre/dVe Model dIfferences  
This Instruction Manual covers two models of  
commercial electric water heaters; DRE models and  
DVE models. These two models are equipped from the  
factory with different controls.  
DRE models are factory equipped with surface mounted  
thermostat/ECO combination controls. DVE models are  
factory equipped with an electronic control system.  
In this Instruction Manual “DRE” models are referred to  
as: “Surface Mount Control” models.  
In this Instruction Manual “DVE” models are referred to  
as: “Electronic Control” models.  
Model number  
DRE/DVE-52  
DRE/DVE-80  
DRE/DVE-120  
tank capacity in Gallons (liters)  
50 (189.3)  
a - Inches (mm) B - Inches (mm) c - Inches (mm)  
Inlet/outlet  
1 1/4  
55 3/4 (1416)  
60 1/4 (1350)  
62 1/4 (1581)  
21 3/4 (552)  
25 1/2 (648)  
29 1/2 (749)  
27 (685)  
31 (787)  
35 (889)  
80 (302.8)  
1 1/4  
119 (450.5)  
1 1/4  
recoVery rate In Gallons per hour*  
temperature rise °f  
standard  
kw Input  
Btu/  
hour  
30°  
40°  
50°  
60°  
70°  
80°  
90°  
100°  
110°  
120°  
130°  
140°  
6
9
20,478  
30,717  
40,956  
46,075  
51,195  
61,434  
81,912  
92,151  
102,390  
122,868  
138,226  
153,585  
184,302  
82  
62  
49  
74  
41  
62  
35  
53  
31  
46  
27  
41  
25  
37  
22  
34  
21  
31  
19  
28  
18  
26  
123  
164  
184  
205  
246  
328  
369  
410  
492  
554  
615  
738  
92  
12  
13.5  
15  
18  
24  
27  
30  
36  
40.5  
45  
54  
123  
138  
154  
184  
246  
276  
307  
369  
418  
461  
553  
98  
82  
70  
61  
55  
49  
45  
41  
38  
35  
111  
123  
148  
197  
221  
246  
295  
3332  
369  
443  
92  
79  
69  
62  
55  
50  
46  
43  
40  
102  
123  
164  
184  
205  
246  
277  
307  
369  
88  
77  
68  
61  
56  
51  
47  
44  
105  
140  
158  
176  
211  
237  
263  
316  
92  
82  
74  
67  
61  
57  
53  
123  
138  
154  
184  
208  
230  
277  
109  
123  
137  
164  
1185  
205  
246  
98  
89  
82  
76  
70  
111  
123  
148  
166  
184  
221  
101  
112  
134  
151  
168  
201  
92  
85  
79  
102  
123  
138  
154  
184  
95  
88  
113  
128  
142  
170  
105  
119  
132  
158  
*Figured at 1 KW (3413 Btu) = 4.1 gallons at 100°F temperature rise.  
To determine recovery rate per minute, divide recovery rate per hour by 60.  
5
approVals  
All models meet  
National Sanitation  
Foundation NSF-5  
requirements.  
All models are listed  
by Underwriters  
Laboratories Inc.  
Model and ratInG  
6
features and coMponents  
electronIc control Models  
fIGure 1  
7
features and coMponents  
surface Mount control Models  
fIGure 2  
8
locatInG the new water heater  
2. Near a floor drain. The heater should be located in an area where  
facts to consIder aBout the locatIon  
leakage of the tank or connections will not result in damage to the  
area adjacent to the heater or to lower floors of the structure.  
3. Close to the point of major hot water usage and the power  
supply.  
Hot water piping and branch circuit wiring should be as short as  
possible.  
Insulate hot and cold water piping where heat loss and condensation  
may be a problem.  
Heater construction permits installation, maintenance, and  
service work to be performed through the front control panel.  
Carefully choose a location for the new water heater. The placement  
is a very important consideration for the safety of the occupants in  
the building and for the most economical use of the appliance.  
Suggested clearances from adjacent surfaces are 12 inches on  
top, 30 inches in front for access to the unit.  
Whether replacing an old water heater or putting the water heater in  
a new location, the following critical points must be observed. The  
water heater must be located:  
The heater may be installed on or against combustible surfaces. The  
left side and back may be placed flush against adjacent surfaces.  
1. On a level surface. Shim the channel type skid base as necessary  
if levelling is required.  
The temperature of the space in which the water heater is installed  
must not go below 32°F or above 122°F.  
9
InstallatIon  
reQuIred aBIlIty  
contaMInated water  
Installation and service of this water heater requires ability equivalent  
to that of a qualified agency (page 2) in the field involved. Plumbing  
and electrical work is required.  
This water heater shall not be connected to any heating  
system(s) or component(s) used with a non-potable water  
heating appliance.  
General  
Toxic chemicals, such as those used for boiler treatment shall not  
be introduced into this system.  
The installation must conform with these instructions and the  
local code authority having jurisdiction and the requirements of the  
power company. In the absence of code requirements, follow NFPA-  
70 (current edition). In the absence of local codes, the installation  
must comply with the latest editions of the National Electrical Code,  
NFPA 70 or the Canadian Electrical Code CSA C22.1. The National  
Electrical Code may be ordered from: National Fire Protection  
Association, 1 Batterymarch Park, Quincy, MA02269. The Canadian  
Electrical Code is available from the Canadian StandardsAssociation,  
8501 East Pleasant Valley Road, Cleveland, OH 44131.  
cIrculatInG puMp  
Field installed circulating pumps should be of all bronze  
construction.  
InsulatIon Blankets  
Do not test electrical system before heater is filled with water, follow  
the START UP procedure in the OPERATION section of this manual.  
Insulation blankets are available to the general public for  
external use on electric water heaters but are not necessary with  
this product. The purpose of an insulation blanket is to reduce  
the standby heat loss encountered with storage tank heaters.  
Your water heater meets or exceeds the EPACT and ASHRAE/  
IES 90.1 standards with respect to insulation and standby loss  
requirements, making an insulation blanket unnecessary.  
The principal components of the heater are identified in the  
Features and Components illustrations on pages 6 and 7.  
Should you choose to apply an insulation blanket to this heater,  
you should follow these instructions below. Failure to follow  
these instructions can result in fire, serious personal injury,  
or death.  
• Do not cover the temperature and pressure relief (T & P) valve  
with an insulation blanket.  
• Do not cover the instruction manual. Keep it on the side of the  
water heater or nearby for future reference.  
• Do obtain new warning and instruction labels for placement on  
the blanket directly over the existing labels.  
MIXING VALVE USAGE:  
Water heaters are intended to produce hot water. Water heated to  
a temperature which will satisfy space heating, clothes washing,  
dish washing, cleaning and other sanitizing needs can scald and  
permanently injure you upon contact. Some people are more likely  
to be permanently injured by hot water than others. These include  
the elderly, children, the infirm, or physically/developmentally  
disabled. If anyone using hot water in your home fits into one of these  
groups or if there is a local code or state law requiring a maximum  
water temperature at the hot water tap, then you must take special  
precautions. In addition to using the lowest possible temperature  
setting that satisfies your hot water needs, a means such as a  
MIXInG ValVe, should be used at the hot water taps used by these  
people or at the water heater.  
teMperature-pressure relIef ValVe  
MIXInG ValVes for reducing point of use temperature are  
available. Consult a qualified installer or service agency. Follow all  
manufacturer’s Instructions for installation of these valves. Before  
changing the factory setting on the thermostat, read the “Temperature  
Regulation” section in this manual.  
This water heater is provided with a properly rated/sized and  
certified combination temperature - pressure relief valve by the  
10  
manufacturer. The valve is certified by a nationally recognized  
testing laboratory that maintains periodic inspection of production  
of listed equipment of materials as meeting the requirements  
for Relief Valves for Hot Water Supply Systems, ANSI Z21.22 •  
CSA 4.4, and the code requirements of ASME.  
If replaced, the new valve must meet the requirements of local  
codes, but not less than a combination temperature and pressure  
relief valve rated/sized and certified as indicated in the above  
paragraph. The new valve must be marked with a maximum set  
pressure not to exceed the marked hydrostatic working pressure  
of the water heater (150 psi = 1,035 kPa) and a discharge  
capacity not less than the water heater Btu/hr or KW input rate  
as shown on the water heater’s model rating plate.  
The temperature-pressure relief valve must be manually  
operated at least once a year. Caution should be taken to  
ensure that (1) no one is in front of or around the outlet of the  
temperature-pressure relief valve discharge line, and (2) the  
water manually discharged will not cause any bodily injury or  
property damage because the water may be extremely hot. If  
after manually operating the valve, it fails to completely reset  
and continues to release water, immediately close the cold water  
inlet to the water heater, follow the draining instructions in this  
manual, and replace the temperature-pressure relief valve with  
a properly rated/sized new one.  
For safe operation of the water heater, the temperature and  
pressure relief valve must not be removed from its designated  
opening nor plugged. The temperature-pressure relief valve  
must be installed directly into the fitting of the water heater  
designed for the relief valve. Install discharge piping so that any  
discharge will exit only within 6 inches (15.2 cm) above, or at any  
distance below the structural floor. Be certain that no contact is  
made with any live electrical part. The discharge opening must  
not be blocked or reduced in size under any circumstances.  
Excessive length, over 30 feet (9.14 m), or use of more than  
four elbows can cause restriction and reduce the discharge  
capacity of the valve.  
If you do not understand these instructions or have any questions  
regarding the temperature-pressure relief valve call the toll free  
number listed on the back cover of this manual for technical  
assistance.  
No valve or other obstruction is to be placed between the relief  
valve and the tank. Do not connect discharge piping directly to  
the drain unless a 6” (15.2 cm) air gap is provided. To prevent  
bodily injury, hazard to life, or property damage, the relief valve  
must be allowed to discharge water in adequate quantities should  
circumstances demand. If the discharge pipe is not connected  
to a drain or other suitable means, the water flow may cause  
property damage.  
water lIne connectIons  
This manual provides detailed piping installation diagrams (see  
back section of this manual) for typical methods of application.  
For the heater inlet and outlet connections, di-electric unions are  
recommended. The water heater may be installed by itself, or with a  
separate storage tank, on both single and two-temperature systems.  
When used with a separate storage tank, the circulation may be either  
by gravity or by means of a circulating pump. When a circulating  
pump is used it is important to note that the flow rate should be slow  
so that there will be a minimum of turbulence inside the heater.  
closed water systeMs  
Water supply systems may, because of code requirements or  
such conditions as high line pressure, among others, have  
installed devices such as pressure reducing valves, check valves,  
and back flow preventers. Devices such as these cause the water  
system to be a closed system.  
The Discharge Pipe:  
therMal eXpansIon  
• Shall not be smaller in size than the outlet pipe size  
of the valve, or have any reducing couplings or other  
restrictions.  
As water is heated, it expands (thermal expansion). In a closed  
system the volume of water will grow when it is heated.As the volume  
ofwatergrowstherewillbeacorrespondingincreaseinwaterpressure  
due to thermal expansion. Thermal expansion can cause premature  
tank failure (leakage). This type of failure is not covered under the limited  
warranty. Thermal expansion can also cause intermittent temperature-  
pressure relief valve operation: water discharged from the valve due to  
excessive pressure build up. This condition is not covered under the  
limitedwarranty.Thetemperature-pressure relief valve is not intended  
for the constant relief of thermal expansion.  
• Shall not be plugged or blocked.  
• Shall be of material listed for hot water distribution.  
• Shall be installed so as to allow complete drainage of both the  
temperature-pressure relief valve and the discharge pipe.  
A properly sized thermal expansion tank should be installed  
on all closed systems to control the harmful effects of thermal  
expansion. Contact a local plumbing service agency to have a  
thermal expansion tank installed.  
• Shall terminate at an adequate drain.  
• Shallnothaveanyvalveorotherobstructionbetweentherelief  
valve and the drain.  
11  
electrIcal  
General  
The installation must conform with these instructions and the local code authority having jurisdiction and the requirements of the power  
company. In the absence of local codes, the installation must comply with the current editions of the National Electrical Code, NFPA 70 or  
the Canadian Electrical Code CSA C22.1.  
An electrical ground is required to reduce risk of electrical shock or possible electrocution. The water heater should be connected to a  
separate grounded branch circuit with over-current protection and disconnect switch. The water heater should be grounded in accordance  
with national and local codes.  
Voltage applied to the heater should not vary more than +5% to -10% of the model and rating plate marking for satisfactory operation.  
taBle 310-16. allowable ampacities of Insulated conductors  
Not more than three conductors in raceway, cable, or earth (directly buried), based  
on ambient temperature of 30°C (86°F)  
+The load current rating and the overcurrent protection for these conductors shall not exceed 15 amperes for 14 AWG. 20 amperes for 12 AWG.  
and 30 amperes for 10 AWG copper; or 15 amperes for 12 AWG and 25 amperes for 10 AWG aluminum and copper-clad aluminum.  
*For dry locations only. See 75°C column for wet locations.  
12  
limiting, a UIM (User Interface Module) for user interface & information  
display and element current sensors for monitoring the power circuits.  
Refer to the control circuit label on the water heater for details.The CCB  
ispoweredbyasmall120V/24Vtransformer.Thecontrolcircuitoperates  
on 120V supplied by a larger 100VA transformer. Standard equipment  
includes control circuit fusing using two, 3 amp, class G fuses with 600  
volt rating. Do not substitute fuses of a different rating.  
aMperaGe taBle/oVercurrent protectIon  
The tables above provides the total connected heating element load  
in amperes for branch circuit conductor and overcurrent protection  
sizing. Single-phase heaters are two wire circuits. Three-phase  
heaters are three wire circuits. In addition to the foregoing, a  
grounded conductor is required.  
The rating of the overcurrent protection must be computed on the basis  
of 125% of the total connected load amperage. Where the standard  
ratings and settings do not correspond with this computation, the next  
higher standard rating or setting should be selected.  
Sequence of Operation  
1. When the control is powered, the UIM should display model  
information, water temperature, Operating Set Point, heating  
status and operating mode.  
2. If the control determines that the actual water temperature inside  
the tank is below the programmed Operating Setpoint minus the (1st)  
differential, a call for heat is activated.  
3. After all safety checks are verified, the CCB will energize contactor  
coils starting with the lower bank of heating elements (each  
diagonalrowofthreeheatingelementsisconsideredabank-see  
Figure1)thenenergizethemiddlebank(ifsoequipped)andtopbank  
(if so equipped). The middle and top banks (if so equipped) are  
energized according to programmed 2nd and 3rd differential  
set points.  
4. The control remains in the heating mode until the water temperature  
reaches the programmed Operating Setpoint. At this point the  
contactors will be de-energized in the reverse order.  
5. The control system now enters the standby operating mode while  
continuing to monitor the water temperature and the state of other  
system devices. If the water temperature drops below the  
programmedOperatingSetpointminusthe(1st)differential,thecontrol  
will automatically return to step 2 and repeat the heating cycle.  
heater cIrcuIts - electronIc control Models  
The water heater’s electrical components are pictured and identified  
in Figures 1 and 2. The model and rating plate illustration on page 4  
identifies heater circuit ratings. The ELECTRONIC CONTROLmodel  
has two electrical circuits.  
The control circuit, which controls the electrical power to heating  
elements, referring the following control circuit diagram Figure 3.  
The power circuit, which is operated by the control circuit carries  
the electrical load of the heating elements. The following  
describes the heater circuits and includes wiring diagrams for  
Delta configuration, refer to the “WYE Configuration Insert” for  
water heaters operating at 380V/400V/416V/575V. All heater  
circuits are designed for 50/60 cycle alternating current.  
control cIrcuIt- electronIc control Models  
These models are equipped with an electronic control system. The  
system includes a CCB (Central Control Board) circuit board, an  
immersion temperature probe with ECO for temperature sensing and  
NOTE: See the Electronic Control Models Operation section for more  
detailed information on temperature settings mentioned above.  
120 Vac control cIrcuIt transforMer connectIons - electronIc control Models  
13  
wIrInG dIaGraMs  
ccB (central control Board) cIrcuIt Board  
control cIrcuIt dIaGraM - electronIc control Models  
fIGure 3.  
14  
wIrInG dIaGraMs  
power cIrcuIt dIaGraMs - electronIc control Models  
The water heater’s electrical components are pictured and identified on page 7. The following describes the heater circuits and includes wiring  
diagrams. All heater circuits are designed for 60/50 hertz alternating current. The water heater circuit wiring is 12 AWG, AWM, or TEW type,  
rated 600 volts, 105°C. Fusing consists of three 30 amp fuses for each contactor. Fusing is an optional feature for Canadian models.  
three eleMents - sInGle and three phase  
sIX eleMents - sInGle and three phase  
dIaGraM 1.  
15  
wIrInG dIaGraMs  
nIne eleMent - sInGle and three phase  
dIaGraM 2.  
conVersIon to sInGle phase  
conVersIon to three phase  
When the heater is shipped for connection to a three-phase electrical  
service, it may be connected to a single-phase electrical service of  
the same voltage by:  
When heater is shipped for connection to a single-phase electrical  
service, it may be connected to a three-phase electrical service of  
the same voltage by:  
1. Disconnect blue wires and yellow wires from terminal L3.  
2. Reconnect all blue wires to terminal L1 (with black wires).  
3. Reconnect all yellow wires to terminal L2 (with red wires).  
4. Connect incoming power to terminals L1 and L2.  
1. Disconnect blue wires from terminal L1.  
2. Disconnect yellow wires from terminal L2.  
3. Reconnect all blue wires and yellow wires to terminal L3.  
4. Connect incoming power to terminals L1, L2, and L3.  
16  
wIrInG dIaGraMs  
power cIrcuIt dIaGraMs - surface Mount control Models  
The water heater’s electrical components are pictured and identified on page 8. The following describes the heater circuits and includes  
wiring diagrams. All heater circuits are designed for 60/50 hertz alternating current. The water heater circuit wiring is 12 AWG, AWM, or TEW  
type, rated 600 volts, 105°C. Fusing consist of two 30 amp fuses for each element. Fusing is an optional feature for Canadian models.  
dIaGraM 3.  
17  
wIrInG dIaGraMs  
nIne eleMents - sInGle and three phase  
dIaGraM 4.  
conVersIon to sInGle phase  
conVersIon to three phase  
When the heater is shipped for connection to a three-phase electrical  
service, it may be connected to a single-phase electrical service of  
the same voltage by:  
When heater is shipped for connection to a single-phase electrical  
service, it may be connected to a three-phase electrical service of  
the same voltage by:  
1. Disconnect blue wires from terminal L2.  
1. Disconnect blue wires from terminal L1  
2. Connect all blue wires to terminal L1 (with black wires).  
3. Disconnect all red wires from terminal L3.  
2. Disconnect red wires from terminal L2.  
3. Connect all blue wires to terminal L2 (with yellow wires).  
4. Connect red wires to terminal L3.  
4. Connect all red wires to terminal L-2 (with yellow wires).  
5. Connect incoming power to terminals L1 and L2.  
5. Connect incoming power to terminals L1, L2 and L3.  
18  
operatIon  
InItIal start up  
General  
The following checks should be made by the installer when the  
heater is placed into operation for the first time.  
Refer to the Features and Components section of this manual  
(pages 7 & 8) for the location of components mentioned in the  
instructions that follow.  
1. Turn off the electrical disconnect switch.  
2. Open the front panel, check all water and electrical connections for  
tightness.Also check connections on top and side of heater. Repair  
water leaks and tighten electrical connections as necessary.  
3. Depress the red manual reset button on each Thermostat/ECO  
combination control (Surface Mount Control Models only).  
4. Turn on the electrical disconnect switch.  
5. Observe the operation of the electrical components during the first  
heating cycle. Use care as the electrical circuits are energized.  
6. Close the front panel.  
NEVER turn on power to the water heater without being certain the  
water heater is filled with water and a temperature and pressure  
relief valve is installed in the relief valve opening.  
do not test electrIcal systeM Before heater Is  
fIlled wIth water. follow fIllInG and start-up  
InstructIons In operatIon sectIon.  
Temperature control and contactor operation should be checked  
by allowing heater to come up to temperature and shut  
off automatically. use care as the electrical circuits are  
energized.  
draInInG the water heater  
The water heater must be drained if it is to be shut down and  
exposed to freezing temperatures. Maintenance and service  
procedures may also require draining the heater.  
1. Turn off the electrical disconnect switch.  
2. Close the supply water inlet valve to heater.  
3. Attach hose to outlet opening of drain valve and direct end  
to drain.  
fIllInG the water heater  
4. Open a nearby hot water faucet and the heater drain valve.  
5. If the heater is being drained for an extended shutdown, it is  
suggested the drain valve be left open during this period. The  
hose may be removed.  
Follow FILLING instructions when restoring hot water service.  
1. Turn off the electrical disconnect switch.  
2. Close the water heater drain valve.  
3. Open a nearby hot water faucet to permit the air in the system  
to escape.  
4. Fully open the cold water inlet pipe valve allowing the heater  
and piping to be filled.  
5. Close the hot water faucet as water starts to flow. The heater is  
now ready for STARTUP and TEMPERATURE REGULATION.  
19  
teMperature reGulatIon  
Setting the water heater temperatures at 120°f will reduce the  
risk of scalds. Some States require settings at specific lower  
temperatures.  
hIGh teMperature lIMIt controls (eco)  
Both the ELECTRONIC CONTROL and SURFACE MOUNT  
CONTROLmodel water heaters are equipped with one or more ECO  
(energy cut off) non adjustable high temperature limit control(s). An  
ECO is a normally closed switch that opens (activates) on a rise  
in temperature. If the ECO switch contacts open (activate) due to  
abnormally high water temperatures it will lock-out and disable further  
heating element operation. It is important that a qualified service  
agent be contacted to determine the reason for the ECO activation  
before resetting the ECO. Once the reason has been determined  
and corrected the ECO(s) can be reset as follows:  
therMostat settInGs - surface Mount control  
surface Mount control Models  
Surface Mount Control models have multiple surface mounted  
Thermostat/ECO combination controls. One for each installed heating  
element-seetheSurfaceMountControlwiringdiagramsinthismanual.  
The ECO high temperature limit switch contacts on each control will  
open when the tank temperature reaches approximately 200°F/93°C.  
When the ECO switch contacts open (activate) voltage to ONE heating  
element ONLY is terminated to prevent further heating operation of  
that element. Voltage may still be present at other heating elements  
and they may still be heating the water.  
These models have multiple thermostat/ECO combination controls  
one for each heating element installed. These thermostats are set from  
the factory at 140°F/60°C. Set the thermostat dial at the lowest setting  
which produces an acceptable hot water supply. This will always give  
the most energy efficient operation.  
The ECO is a manual reset switch. Should one or more ECO  
activate, the tank temperature must drop below 120°F/49°C before  
an ECO can be reset. To manually reset an ECO:  
1. Disconnect the power supply to the water heater.  
2. Allow the tank temperature to cool below 120°F/49°C.  
3. Remove the front control cover from the effected control(s).  
4. Press the manual reset button on each of the effected controls.  
Once the control(s) has been reset the control cover should be  
replaced prior to restoring power to the water heater.  
electronic control Models  
The ECO high temperature limit switch is located inside the  
immersion Temperature Probe (two red wires) on ELECTRONIC  
CONTROL models. The ECO switch contacts will open when the  
water temperature reaches approximately 202°F/94°C. When  
the ECO switch contacts open (activate) the electronic control  
system locks out and displays a Fault message. Voltage to the  
contactor coils and heating elements is terminated to prevent  
further heating operation.  
Should the ECO activate, the water temperature must drop below  
140°F/60°C before the control system can be reset. Once the water  
temperature has cooled below this point the power supply to the water  
heater must be turned off and on again to reset the control system.  
Figure 4 shows the approximate time-to-burn relationship for normal  
adult skin.  
therMostat controls  
The water heaters covered in this instruction manual are equipped  
with adjustable thermostat controls to control water temperature.  
Hot water temperatures required for automatic dishwasher and  
laundry use can cause scald burns resulting in serious personal  
injury and/or death. The temperature at which injury occurs  
varies with the persons age and duration of exposure. The  
slower response time of children, the elderly or disabled persons  
increases the hazards to them. Never allow small children to use  
a hot water tap or draw their own bath water. Never leave a child  
or disabled person unattended in a bathtub or shower.  
Temperature  
Settings  
Time to Produce 2nd & 3rd  
Degree Burns on Adult Skin  
180°F (82°C)  
160°F (71°C)  
150°F (66°C)  
140°F (60°C)  
130°F (54°C)  
120°F (49°C)  
80°F (27°C)  
Nearly Instantaneous  
About 1/2 second  
About 1-1/2 seconds  
Less than 5 seconds  
About 30 seconds  
More than 5 minutes  
- - - - - - - - - - - - - - - -  
The water heater should be located in an area where the general  
public does not have access to set temperatures.  
fIGure 4  
20  
The Operating Set Point is adjustable from 90°F/42°C to 190°F/88°C.  
The factory setting is 120°F/49°C. See the Electronic Control Models  
Operation section of this manual for instructions on how to adjust  
the Operating Set Point and other user settings.  
therMostat settInGs - electronIc controls  
These models are equipped with an electronic control system. The  
control system senses temperature from a factory installed Immersion  
Temperature Probe (see Figure 1). The “Operating Set Point” is  
adjustedtocontrolwatertemperature.Thisisanadjustableusersetting  
in the control system’s “Temperatures Menu.” This and all control  
system menus are accessed through the UIM (User Interface Module  
- see Figure 5) located on the front panel of the water heater.  
uIM (user Interface Module)  
fIGure 5  
Set the Operating Set Point at the lowest setting which produces  
an acceptable hot water supply. This will always give the most  
energy efficient operation.  
electronIc control Models operatIon  
up & down Buttons  
control systeM features  
Used to navigate (up and down) and to select (highlight) menu items.  
Also used to adjust or change (increase/decrease, on/off, set time)  
various user settings.  
Advanced Diagnostics: Plain English text and animated icons display  
detailed operational and diagnostic information. LCD screen on the  
front of the water heater displays the Sequence of Operation in real  
time. FaultorAlertmessagesaredisplayedwhenoperationalproblems  
occur. Advanced Service menu displays a list of possible causes for  
current Fault and Alert conditions to aid in servicing.  
operational Buttons  
The 3 Operational Buttons are multifunctional. Their current function is  
defined by the text that appears above each button on the LCD screen.  
Thefunctionwillchangedependingonwhatmenuiscurrentlydisplayed  
or what menu item is selected. When no text appears on the LCD  
screen above an Operational Button there is no function assigned.  
Economy Mode Operation: Control system automatically lowers  
the Operating Set Point by a programmed value during user defined  
time periods. Helps reduce operating costs during unoccupied or  
peak demand periods.  
the desktop screen  
Linear Sequencing: Banks of heating elements (3 elements per  
bank) are energized according to adjustable (1 to 20°) differential  
set points for each bank. First bank on is the last bank off. Helps  
reduce operating costs during low/moderate loads.  
Figure 7 below shows the control system “Desktop Screen.” This  
is the default screen. If there are no active Fault or Alert conditions  
and no user input for approximately 10 minutes the control system  
will return to this screen automatically.  
control systeM naVIGatIon  
Model Information  
The UIM (User Interface Module) is located on the front cabinet of the  
Electronic Control Model water heaters. All operational information  
and user settings are displayed and accessed using the UIM. The  
UIM includes five snap acting (momentary) user input buttons; an  
Up, Down and 3 Operational Buttons.  
Model information and menu titles are shown in the black bar at the  
top of the Desktop Screen.  
tank temperature  
Current water temperature as sensed from the immersion  
Temperature Probe.  
Operating Set Point: Temperature at which the control system will  
maintain tank (water) temperature in the Normal Mode. This line of  
text will read economy set point whenever the control system is  
operating in the Economy Mode.  
Status: The Operating State of the control system is displayed  
beneath the Operating Set Point.  
uIM - user Interface Module  
fIGure 6.  
fIGure 7.  
21  
Menu: The left Operational Button is pressed to enter the Main Menu  
where all control system menus are accessed. See Table 3 for a list  
of control system menus.  
are adjusted in the Economy Mode Setup menu. The current  
Operating Mode, either Normal Mode or Economy Mode, is  
displayed beneath the day and time.  
Help: The right Operational Button is pressed to access instructions  
and explanations for user settings, Operating States, Status Icons,  
manufacturer’s web address, technical support phone number and  
service agent contact information.  
Discreet Menu Contact Information: From the Desktop Screen  
press and hold down the middle (unmarked) Operational Button for  
30 seconds and then release it. This will launch a discreet menu  
where personalized contact information can be entered. Installing  
contractors and/or service agents can enter their company name  
and telephone number. This contact information will be displayed  
with all Fault and Alert messages.  
Day/Time/Operating Mode: The current time and day are  
also displayed on the Desktop Screen. “Clock Not Set” will be  
displayed until the time clock has been initially set. Day and Time  
taBle 1 status Icons.  
Icon  
descrIptIon  
Water temperature in the tank has fallen. Shaded area of the animated thermometer icon will rise and fall in  
response to water temperature in the storage tank as sensed from the immersion Temperature Probe.  
Water temperature in the tank has reached the Operating Set Point. Shaded area of the animated thermometer  
icon will rise and fall in response to water temperature in the storage tank as sensed from the immersion  
Temperature Probe.  
The control is unable to initiate a heating cycle. This will happen whenever a Fault condition is detected by the  
control system or when either of the two Enable/Disable circuits are open circuits.  
The control system is in Heating Mode and has energized the electromagnetic contactor coils for at least one bank  
of heating elements. This animated icon DOES NOT indicate current has been sensed from the heating elements,  
only that there is a call for heat present and the control system has initiated heating operation.  
Heating elements icon for a water heater equipped with 1 Bank of heating elements. Each circle represents one  
heating element. Each diagonal row of 3 elements = 1 Bank of elements. Open circles represent heating elements  
the control system has not energized and is not sensing electrical current from.  
Heating elements icon for a water heater equipped with 2 Banks of heating elements. Each circle represents one  
heating element. Each diagonal row of 3 elements = 1 Bank of elements. Open circles represent heating elements  
the control system has not energized and is not sensing electrical current from.  
Heating elements icon for a water heater equipped with 3 Banks of heating elements. Each circle represents one  
heating element. Each diagonal row of 3 elements = 1 Bank of elements. Open circles represent heating elements  
the control system has not energized and is not sensing electrical current from.  
Heating elements icon for a water heater equipped with 3 Banks of heating elements. Each circle represents one  
heating element. Each diagonal row of 3 elements = 1 Bank of elements. Filled circles represent heating elements  
the control system has energized AND is sensing electrical current from.  
Heating elements icon for a water heater equipped with 3 Banks of heating elements. Each circle represents one  
heating element. Each diagonal row of 3 elements = 1 Bank of elements. Open circles with an X represent heating  
elements the control system has energized that it IS NOT sensing electrical current from.  
The control has detected/declared a Fault Condition. Fault message details can be viewed in the Current Fault  
menu. Heating operation is discontinued (locked out) until the condition that caused the fault is corrected. Power to  
the water heater must be cycled off and on to reset the control system. Note; cycling power will not reset the control  
system if the condition that caused the fault has not been corrected.  
The control has detected/declared an Alert Condition. The water heater will continue to operate during an Alert  
Condition but there is an operational condition that requires the attention of a Qualified ServiceAgent.Alert message  
details can be viewed in the Current Alert menu.  
22  
taBle 2 operatInG states.  
descrIptIon  
state  
The water heater is not in an active heating cycle. This usually indicates the temperature in the tank has reached  
the Operating Set Point and the control system has terminated the heating cycle.  
Standby  
Heating  
Alert  
The control system is in the Heating Mode. At least one bank of heating elements has been energized.  
The control system has detected/declared an Alert Condition. The controls system will continue heating operation.  
However, a Qualified Service Agent should be contacted to check/service the water heater.  
The control system has detected/declared a Fault Condition. The control system will discontinue heating operation  
and “lock out.” Power to the water heater must be cycled off and on to reset the control system. Note; cycling power  
will not reset the control system until the condition that caused the fault has been corrected.  
Fault  
taBle 3 control systeM Menus.  
descrIptIon  
Menus  
Most commonly accessed menu. Operating Set Point, Differential settings, Tank Temperature and Tank Probe  
Offset are located in this menu.  
Temperatures  
Current Operating State/Mode (heating/standby etc) and status (open/closed - on/off - yes/no) of monitored water  
heater functions and components are displayed in this menu.  
Heater Status  
Economy Mode  
Seven day 24 hour time clock with temperature set back capability to reduce operating costs during unoccupied  
or reduced demand periods.  
Setup  
The control system’s CCB (Central Control Board) features on board SPDT (single pole double throw) relay contacts  
for building EMS (Energy Management System) notification of operational conditions such as Fault Conditions and  
heating mode status. This menu features a list of user definable conditions for relay activation.  
Alarm Output  
Setup  
Temperature units (°F or °C), appearance (brightness contrast) and backlight delay user adjustable settings are  
located in this menu.  
Display Settings  
Elapsed time of operation, total heating cycle time, heating cycle count, heating element bank(s) cycle count and  
heating bank on time along with UIM and CCB software revisions can be viewed in this menu.  
Heater Information  
Current Fault/Alert  
Fault History  
Displays any current Alert or Fault messages.  
Retains 9 event history of Fault/Alert messages with time stamp.The Fault History is useful when dealing with intermittent  
operational problems or when the customer has reset the control system prior to a service agent’s arrival.  
Running total of all Fault and Alert Conditions that have occurred are displayed in this menu. Can help determine  
potential root cause(s) of related operational problems.  
Fault Occurrence  
Restore Factory  
This control system feature allows the user to restore control system user settings to their factory default settings.  
Alarm Output Setup and Display Settings menu items ARE NOT changed when factory defaults are restored.  
Defaults  
Accessible by pressing the corresponding Operational Button from most menus and screen displays. This menu  
provides access to instructions and explanations for user settings, Operating States, Status Icons, manufacturer’s  
web address, technical support phone number and service agent contact information.  
Help Menu  
teMperatures Menu  
operating set point  
User adjustable setting 90°F to 190°F range; factory default is  
120°F. When the water temperature sensed by the control system  
from the immersion Temperature Probe reaches the Operating Set  
Point the control system will end the heating cycle. A call for heat  
will be activated again when the water temperature drops below the  
Operating Set Point minus the 1st Differential Setting.  
Example: Operating Set Point is 120°F, the 1st Differential Setting is  
2°F (factory default).Acall for heat will be activated when the sensed  
water temperature drops to 118°F.  
23  
differential settings  
tank temperature  
Adjustable user setting(s) 1°F to 20° range; factory default is 2°F.  
The water heaters covered in this Instruction Manual will have 3, 6 or  
9 heating elements. Each group of 3 heating elements is one “Bank” of  
heating elements. Heating elements are energized in Banks of 3. Each  
Bank of heating elements will have a Differential Setting associated  
with it. Differential Settings are located in the Temperatures Menu.  
Nonadjustableinformationdisplay.Currentwatertemperatureassensed  
by the control system from the immersion Temperature Probe.  
tank probe offset  
User adjustable setting -5°F to +5°F range; factory default is 0°F. If the  
current Tank Temperature is sensed (from the immersion Temperature  
Probe) at 120°F and the offset is adjusted to -5°F the control system  
would calibrate or “offset” theTankTemperature to 115°F. Heating cycles  
would then start/stop based on the calibrated Tank Temperature.  
There is a 1st Differential Setting on all models. There will be one  
additional Differential Setting visible/adjustable for each additional  
Bank of (3) heating elements.  
operating sequence  
Used to calibrate for slight differences in control system temperature  
sensing. This can improve the precision of temperature control in  
the storage tank and at points of use. This feature can also be  
used to compensate for building recirculation loops (hot water  
returning to the storage tank) that may cause the heating cycle to  
terminate prematurely.  
With an Operating Set Point of 120°F and all Differential settings at 2°F  
the On/Off sequencing of heating element Banks would be as follows:  
DIFFERENTIAL  
SETTING  
TURN ON  
TEMP  
TURN OFF  
TEMP  
BANK NUMBER  
teMperature settInGs  
Bank 1  
Bank 2  
Bank 3  
2°F  
2°F  
2°F  
118°F  
116°F  
114°F  
120°F  
118°F  
116°F  
The Operating Set Point and the Differential Settings are adjusted  
in the Temperatures Menu. The following instructions explain how to  
adjust these user settings and navigate the control system menus.  
actIon  
dIsplay  
From the Desktop Screen, press the Operational Button underneath “MENU”  
to enter the Main Menu.  
Notice how the text above the Operational Buttons on the display changes  
as you navigate through the various menus and screens.  
With Temperatures selected (highlight in black) in the Main Menu, press  
the Operational Button underneath “SELECT” to enter the Temperatures  
Menu.  
If Temperatures is not selected use the Up and Down buttons to select this  
menu item.  
With the Operating Set Point selected in the Temperatures Menu, press  
the Operational Button underneath “CHANGE” to activate the adjustment  
mode for this menu item.  
Press the Up and Down buttons to adjust the Operating Set Point to the  
desired setting.  
Press the Operational Button underneath “UPDATE” to confirm the new  
setting. Press the Operational Button underneath “CANCEL” to discard the  
new setting and retain the previous setting.  
The new Operating Set Point value should now be displayed as the current  
value.  
NOTE: Use this same procedure to adjust the Differential settings and the  
Tank Probe Offset in the Temperatures Menu.  
This same procedure is used to change user settings in other control system  
menus.  
24  
alarm condition  
heater status Menu  
Displays the status of the user definableAlarm Output function - see  
Alarm Output Setup Menu. Yes = alarm condition has been met, No  
= alarm condition has not been met.  
This menu displays non adjustable operational information. This  
menu contains more information that can be displayed on one screen  
of the LCD display. Use the Up & Down Buttons to navigate to the  
bottom of this menu.  
alarm relay output  
top of Menu  
Displays the state of the normally open contacts of theAlarm Output  
relay. This relay (J3 contacts on the CCB) is used for building EMS  
(Energy Management System) notification of operational conditions  
such as Fault conditions.  
econoMy Mode setup Menu  
This menu contains settings used to establish an “Economy Set  
Point” and “Economy Mode” operating periods. This control system  
feature can help reduce operating costs during unoccupied, low load,  
or peak demand periods.  
desktop screen during economy Mode  
Bottom of Menu  
economy Mode setup Menu  
status  
Displays the current Operating State of the control system. IE:  
Heating, Standby, Fault see Table 2.  
element Banks on  
Displays the current number of heating element Banks the control  
system has energized. Each Bank of elements contains 3 heating  
elements.  
eco contact  
setpoint adjustment  
Displays the current state of the ECO high temperature limit  
switch contacts. The ECO switch is located inside the immersion  
Temperature Probe (two red wires).  
Adjustable user setting (2°F to 50°F - factory default is 20°F) the  
control systemusestocalculatetheEconomySetPoint.TheEconomy  
SetPoint=normalOperatingSetPointminustheprogrammedSetpoint  
Adjustment value. The Economy Set Point is the water temperature  
the control system maintains during programmed Economy Mode time  
periods. “Economy Set Point” is displayed instead of “Operating Set  
Point” and “Economy Mode” appears beneath the current time on the  
Desktop Screen during Economy Mode time periods.  
enable / disable 1 & 2  
Displays the current state, open or closed, of the two Enable/Disable  
circuits (J7 socket on the CCB - see wiring diagrams) provided  
for external supervisory controls such as building EMS (Energy  
Management System). Both of these Enable/Disable circuits must be  
closed to “enable” heating operation. If either Enable/Disable circuit is  
open for any reason heating operation will be “disabled.” There is a plug  
with two jumper wires installed from the factory in the CCB J7 socket to  
enable heating operation when external controls are not in use.  
current time  
Seven Day 24 hr clock. Use this menu item to set the current time  
and day of the week. Current day and time are not set from the  
factory. “Clock Not Set” will be displayed on the Desktop until the  
time/day has been initially set.  
Service Note: If a supervisory control(s) is used to enable/disable  
heating operation, install field wiring between the J7 socket on the CCB  
and a set of “dry contacts” on the external control per all applicable  
building codes. This is a switching circuit only: DO NOT apply any  
external voltage or connect any load (IE: relay coil) to either circuit.  
heater In economy Mode  
Displays whether the control system is currently operating in  
Economy Mode or not.  
element Bank on  
daily operating Mode (sun - Mon - tue - wed - thu - fri - sat)  
Displays the on/off status of each Bank of heating elements. Yes =  
On, No = Off.  
Seven daily sub menus are listed at the bottom of the Economy Mode  
Setup menu. There are 3 Operating Modes in each sub menu;  
25  
“Normal Operation All Day” - “Economy Mode All Day” and “Normal  
Operation Between.” Only one Operating Mode can be active, the  
factory default is Normal Operation All Day.  
Normal Operation Between: When this operating mode is active  
there will also be start and stop times to program. The normal  
Operating Set Point is used between the programmed start and stop  
times and the Economy Set Point will be in effect during the rest of  
the day. There is one start time and one stop time event per day.  
Normal Operation All Day: When this operating mode is active the  
normal Operating Set Point is used for the entire day.  
econoMy Mode settInGs  
Economy Mode All Day: When this operating mode is active the  
Economy Set Point is used for the entire day.  
setpoint adjustment Value  
actIon  
dIsplay  
From the Desktop Screen, press the Operational Button underneath “MENU”  
to enter the Main Menu.  
Notice how the text above the Operational Buttons on the display changes  
as you navigate through the various menus and screens.  
Use the Up/Down buttons to select (highlight in black) the Economy Mode  
Setup menu from the Main Menu. Press the Operational Button underneath  
“SELECT” to enter the Economy Mode Setup menu.  
Use the Up/Down buttons to select (highlight in black) SetpointAdjustment.  
Press the Operational Button underneath “CHANGE” to activate the  
adjustment mode for the Setpoint Adjustment value.  
Use the Up/Down buttons to change the SetpointAdjustment to the desired  
value. The Setpoint Adjustment value is adjustable from 2°F to 50°F. The  
factory default is 20°F.  
Notice how the text above the Operational Buttons on the display changes  
to “UPDATE” & “CANCEL” when the adjustment mode is activated and how  
the current value is outlined rather than highlighted in black.  
Press the Operational Button underneath “UPDATE” to enter and confirm  
the new value. Pressing the Operational Button underneath “CANCEL”  
would discard the new value and retain the previous value.  
The new Setpoint Adjustment value should now be displayed as the  
current value.  
26  
econoMy Mode settInGs  
time clock settings  
actIon  
dIsplay  
From the Desktop Screen navigate to the Economy Mode Setup menu.  
Use the Up/Down buttons to select (highlight in black) Current Time sub  
menu. Press the Operational Button underneath “CHANGE” to enter the  
Current Time sub menu.  
Use the Up/Down buttons to select the “Weekday” setting.  
Press the Operational Button underneath “CHANGE” to activate the  
adjustment mode for this setting.  
Press the Up and Down buttons to adjust the Weekday setting to the  
current day.  
Notice how the text above the Operational Buttons on the display changes  
to “ACCEPT” & “CANCEL” when the adjustment mode is activated and how  
the current setting is outlined rather than highlighted in black.  
Press the Operational Button underneath “ACCEPT” to enter and confirm  
the new setting. Pressing the Operational Button underneath “CANCEL”  
would discard the new setting and retain the previous setting.  
Use the Up/Down and the CHANGE/ACCEPT Operational Buttons to  
individually select and change the remaining time settings (Hour, Minutes,  
AM/PM) to the current time in the same way as outlined above.  
When finished making changes press the Operational Button underneath  
“BACK” to confirm all new settings and update the control system. The  
display will automatically return to the Economy Mode Setup menu.  
The new settings should be displayed as the Current Time.  
27  
econoMy Mode settInGs  
daily operating Mode settings  
actIon  
dIsplay  
Economy Mode All Day:  
From the Economy Mode Setup menu use the Up/Down buttons to select  
(highlight in black) the Daily sub menu for “Sun.” Press the Operational  
Button underneath “CHANGE” to enter this menu.  
Use the Up/Down buttons to select (highlight in black) the “Economy Mode  
All Day” setting.  
Press the Operational Button underneath “SELECT” to change from the  
factory default Normal Operation All Day setting to the Economy Mode All  
Day setting.  
Press the Operational Button underneath “BACK” to confirm the new setting  
and update the control system. You will be returned to the Economy Mode  
Setup menu. The new setting should now be displayed for Sun.  
Normal Operation Between:  
From the Economy Mode Setup menu Use the Up/Down and CHANGE  
buttons to enter the Mon sub menu.  
Use the Up/Down buttons to select (highlight in black) the “Normal Operation  
Between” setting. Press the Operational Button underneath “SELECT” to  
change the operating mode for Monday to Normal Operation Between.  
Note that when this setting is selected Start and Stop time user settings  
appear on the display.  
Use the Up/Down buttons to navigate between the Start and Stop time Hour,  
Minutes and AM/PM settings.  
With each item selected press the Operational Button underneath “SELECT”  
to activate the adjustment mode for each setting. Use the Up/Down buttons  
to change the value to the desired setting.  
Press the Operational Button underneath “ACCEPT” to enter the new setting  
or “CANCEL” to discard the new setting and retain the previous setting.  
Press the Operational Button underneath “BACK” to confirm the settings  
and update the control system. You will be returned to the Economy Mode  
Setup menu. The new settings should be shown for Mon.  
28  
alarM output setup Menu  
dIsplay settInGs Menu  
Permits user to set display options for viewing information on the  
UIM’s LCD screen.  
Permits user to set the condition (from a list of options) for when  
the CCB’s integral alarm output relay will be energized. Alarm relay  
connections (common, normally open, normally closed) are located  
on the J3 terminal strip on the CCB. Alarm output relay contacts are  
capable of switching 1 amp maximum at 120 VAC.  
The alarm relay operates in the background according to the settings  
in this menu and is not capable of disabling water heater operation.  
The alarm relay is used for external notification/verification of  
various operational conditions such as fault conditions and heating  
mode status. This relay can be used with building EMS (Energy  
Management System) and other external supervisory controls.  
temperature units  
Adjustable user setting that changes temperature units display to  
Celsius °C or Fahrenheit °F.  
Backlight delay  
Adjustable user setting that determines how long the UIM’s LCD  
backlight remains illuminated after a key has been pressed.Available  
settings are; Always Off, 10, 30 or 60 seconds and Always On.  
contrast  
Adjustable user setting to adjust the UIM’s LCD screen contrast  
between text and background.  
display settings  
Changing the user settings in this menu is done using the same  
methods for changing the Operating Set Point.  
service note  
Adjustable user settings in the Display Settings menu are unaffected  
by Restore Factory Defaults.  
heater InforMatIon Menu  
This menu displays non adjustable operational information.  
output function  
Adjustable user setting. Available options for the Alarm Output  
Function setting are:  
Heating Mode: Used for heating mode on/off status notification.  
Enable / Disable Closed: Used for notification and/or verification of  
the enable/disable circuits open/closed status. There are two enable/  
disable circuits available for external supervisory control(s) at the J7  
socket on the CCB - see wiring diagrams. Enable/disable circuit(s)  
status can be viewed in the Heater Status Menu.  
Temp < Heater SP: Used for external notification when current tank  
temperature drops below Operating Set Point.  
Temp < Alarm SP: Used for external notification when current tank  
temperature drops below programmable Alarm SP.  
top of Menu  
Fault or Alert: Used for external notification whenever a Fault or  
Alert condition is active.  
Fault: Used for notification whenever a Fault condition is active.  
Disabled: Disables the Alarm Relay Output Function.  
Alarm SP: Adjustable user setting (90°F to 190°F) the control system  
uses for the “Temp <Alarm SP” function described above. This setting  
has no effect with any other Alarm Output functions.  
Alarm Output Settings: Changing the user settings in this menu is  
done using the same methods for changing the Operating Set Point.  
Service Note: Adjustable user settings in the Alarm Output Setup  
menu are unaffected by Restore Factory Defaults.  
BottoM of Menu  
29  
elapsed time  
This menu displays non adjustable operational information. The  
control system records and stores the last 9 Fault and Alert  
messages in chronological order in this menu. The most recent  
will be at the top of the list. A time stamp is displayed below each  
listed Fault and Alert message showing when the Fault or Alert  
condition occurred.  
Total accumulated time the control system (water heater) has been  
energized.  
total heating time  
Total accumulated time the control system has been in the heating  
mode. IE: any heating elements have been energized.  
The Fault History is useful when dealing with intermittent operational  
problems or when the customer has reset the control system prior  
to a service agent’s arrival.  
Bank # cycles  
Total accumulated count of heating cycles for each Bank of heating elements.  
With a Fault or Alert item selected press the Operational Button  
underneath “VIEW” to display the details for the Fault or Alert  
message. The Fault/Alert message screen displays a brief  
description of the condition, contact information and access to the  
Advanced service information sub menu.  
Bank # on time  
Total accumulated heating on time for each Bank of heating  
elements.  
current / history fault Message  
ccB Version  
Software version for Central Control Board.  
uIM Version  
Software version for User Interface Module.  
current fault / alert Menu  
This menu displays non adjustable operational information. With the  
Fault History sub menu selected in Main Menu; press the Operational  
Button underneath “SELECT” to display the current Fault or Alert  
message. If there is not a Fault or Alert condition currently active  
“(none)” is displayed to the right of this menu.  
Main Menu - current fault selected  
fault occurrence Menu  
Total accumulated number each individual Fault condition has  
occurred is displayed in this menu. This running total of Fault  
Occurrences can be useful in determining which (if any) operational  
problems have been persistent.  
fault occurrence Menu  
fault hIstory Menu  
fault history Menu  
restore factory defaults Menu  
This control system menu allows the user to restore most of the  
control system’s user settings to their factory default settings. User  
settings in the Alarm Output Setup and Display Settings menus are  
unaffected by executing Restore Factory Defaults.  
30  
restore factory defaults  
actIon  
dIsplay  
From the Main Menu use the Up/Down buttons to select (highlight in black)  
the “Restore Factory Defaults” menu.  
Press the Operational Button underneath “SELECT.” The Restore Factory  
Defaults menu will be displayed.  
From the Restore Factory Defaults menu press the Operational Button  
underneath “YES.” The display will show text confirming the factory default  
settings have been restored.  
Press the Operational Button underneath “BACK” to exit the Restore Factory  
Defaults menu.  
MaIntenance  
Periodically the drain valve should be opened and the water  
allowed to run until it flows clean. This will help to prevent  
sediment buildup in the tank bottom.  
General  
Periodically check the temperature and pressure relief valve to ensure  
that it is in operating condition. Lift the lever at the top of the valve  
several times until the valve seats properly and operates freely.  
Water heater maintenance includes periodic tank flushing and  
cleaning, and removal of lime scale from the heating element.  
The heater tank is equipped with an anode rod to aid in corrosion control.  
anode InspectIon and replaceMent  
Inspection of the sacrificial anode every 6 to 12 months allows you  
to identify a spent anode and replace it. Replace the anode when  
31  
its diameter is 3/8” (1 cm) of an inch, or annually which ever is first.  
Aggressive, very hot and softened water causes rapid consumption  
of the anode requiring frequent inspections. Call the toll free number  
on the back cover of this manual for information on obtaining  
replacement anode rods.  
3. Characteristics of water supply.  
Regardless of water treatment, the elements should be examined  
regularly.  
Lime scale accumulations may cause noises to occur during operation.  
It is recommended that a heating element be removed periodically  
for examination. If it is scaled, all of the elements should be removed  
and cleaned. If the tank bottom has an accumulation of sediment it  
should be cleaned.  
MaIntenance schedule  
component  
operation  
Interval  
required  
Tank  
Flushing  
Periodically  
Lime scale should be removed by dissolving the accumulation in  
UN•LIME® delimer. Do not use muriatic or hydrochloric acid base  
deliming solutions to remove lime scale from the elements.  
Elements  
Lime Scale  
Removal  
As needed  
Un•Lime®  
delimer &  
element  
gaskets, Part  
THE PROCESS FOR LIME SCALE REMOVAL IS AS FOLLOWS:  
1. Turn off electrical disconnect switch.  
Tank flushing should be performed in accordance with the above  
schedule. Tank sediment removal and element lime scale removal  
must be performed as needed as determined by periodic inspection.  
Following are the instructions for performing recommended  
maintenance.  
2. Drain the heater following DRAINING instructions.  
3. Open front panel.  
4. Disconnect the element wiring. Try not to disturb the wiring  
unnecessarily and reconnection will be easier.  
5. Unscrew each element.  
flushInG  
6. Remove the elements and gaskets from the openings.  
The water heater drain valve should be opened periodically to help  
prevent sediment buildup on the tank bottom.  
• Use a twisting, pulling action to remove elements scaled beyond  
the size of the tank openings.  
1. Turn off the electrical disconnect switch.  
• Brush loose scale from elements.  
7. Lime scale removal:  
2. Attach hose to outlet opening of drain valve and direct end  
to drain.  
• Place limed ends of heating elements into UN•LIME delimer and  
allow scale to dissolve. Do not permit delimer or water to contact  
heating element electrical terminals.  
• Open the drain valve by turning the hand wheel to the left  
(counterclockwise). Allow water to flow until it runs clean.  
• Silicates, sulfates, and aluminates must be removed by scraping  
or other mechanical means. Lime scale dissolvents will  
not remove these types of scale which are occasionally  
encountered.  
• If water does not flow from opened drain valve, follow  
instructions for sediment removal.  
3. When finished flushing:  
Call the toll free phone number on the back cover of this Instruction  
Manual to purchase UN-LIME and heating element gaskets.  
• Close heater drain valve and remove hose.  
• Turn on electricity.  
OTHER SCALE REMOVAL:  
1. Flush cleaned ends of elements with water when deliming or  
cleaning is completed.  
sedIMent reMoVal  
2. Remove sediment and scale from the tank bottom through  
the access provided by the element openings or drain valve  
opening.  
Water borne impurities consist of fine particles of soil and sand which  
settle out and form a layer of sediment on the bottom of the tank.  
In time, if not removed, the level of sediment might reach the  
heating elements and cause their failure.  
• The cold water inlet valve and drain valve may be opened to  
aid the cleanout process.  
For convenience, sediment removal and element lime scale removal  
should be performed at the same time as follows.  
3. Clean remaining gasket material from tank and element flanges  
Do not reuse original element gaskets.  
4. Put new gaskets on each element and install into tank openings.  
lIMe scale reMoVal  
• Uniformly tighten element bolts. Torque to approximately  
32 ft./lbs.  
Lime scale accumulations on the heating elements is a normal  
condition, common to all immersion type elements. Factors  
which affect the amounts of this formation are:  
5. Attach element wires to connection points from which they were  
removed.  
6. Follow FILLING instructions to restore hot water service.  
1. Amount of hot water used. As the volume of water heated  
increases, more scale results.  
• Check for water leaks around elements and proper operation  
when heater is filled.  
2. Water temperature.As the temperature of the water is increased,  
more scale is deposited on the elements.  
• Close the front panel.  
32  
trouBleshootInG checklIst  
ABNORMAL SOUNDS  
checklIst  
Before calling for service, check the following points to see if the  
cause of trouble can be identified and corrected.  
1. Sediment or lime scale accumulations on the elements causes  
sizzling and hissing noises when the heater is operating.  
• The sounds are normal, however, the tank bottom and  
elements should be cleaned. See the Maintenance section of  
this manual.  
Reviewing this checklist may eliminate the need of a service call and  
quickly restore hot water service. See Figures 1 and 2 in this manual  
to identify and locate water heater components.  
2. Some of the electrical components of the water heater make  
sounds which are normal.  
• Contactors will “click” or snap as the heater starts and stops.  
• Transformers and contacts often hum.  
Water leakage is suspected  
Refer to Leakage Checkpoint on the following page.  
1. Check to see if the heater drain valve is tightly closed.  
2. If the outlet of the relief valve is leaking it may represent:  
• Excessive water temperature.  
• Faulty relief valve.  
not enouGh or no hot water  
• Excessive water pressure.  
1. Be certain the electrical disconnect switch serving the water  
3. Excessive water pressure is the most common cause of relief  
valve leakage. It is often caused by a “closed system”. See  
“Closed Water Systems” and “Thermal Expansion” in the  
Installation section of this manual for more information.  
heater is in the ON position.  
2. Check the fuses.  
• The electrical disconnect switch usually contains fuses.  
• The heater has fusing.  
4. Examine the area around the element for gasket leakage.  
• Tighten the elements or, if necessary, follow the WATER AND  
LIME SCALE REMOVAL procedure to replace the gaskets.  
3. If the water was excessively hot, and is now cold, the high limit  
switch may have activated.  
If you cannot IdentIfy or correct the source of  
MalfunctIon  
• See the Temperature Regulation section of this manual for  
more information on how to reset the ECO high limit  
controls.  
1. Turn the power supply to the water heater off.  
2. Close the supply water inlet valve to the heater.  
4. The capacity of the heater may have been exceeded by a large  
demand for hot water.  
3. Contact a Qualified ServiceAgency in your area. Call the toll free  
phone number on the back cover of this Instruction Manual for  
assistance in locating a service agency in your area.  
• Large demands require a recovery period to restore water  
temperature.  
replaceMent parts  
5. Cooler incoming water temperature will lengthen the time required  
to heat water to the desired temperature.  
Call the toll free phone number on the back cover of this Instruction  
Manual for assistance in locating replacement parts.. When ordering  
parts, specify complete model no., serial no., (see rating plate),  
quantity and name of part desired. Standard hardware items should  
be purchased locally.  
6. Look for hot water leakage.  
7. Sediment or pipe scale may be affecting water heater operation.  
33  
leakaGe checkpoInts  
INSTRUCTIONS: USE THIS ILLUSTRATION AS A GUIDE WHEN CHECKING FOR SOURCES OF WATER LEAKAGE.  
Where possible, remove or lift top cover to  
examine threads of fittings installed into tank  
for evidence of leakage. Correct fitting leaks  
as necessary.  
Relief valve operation and leakage may be  
due to water expansion during heating cycle  
or foreign material on seat of valve. If the valve  
is not piped to an open drain, the released  
water could be mistaken for a leaking heater.  
To check where threaded portion enters tank,  
insert Q-tip or similar absorbent material  
between jacket opening and valve to swab  
spud area. Remove valve* if leak is indicated  
and repair with pipe joint compound.  
Water on the side of the tank may be  
condensation due to the panel or insulation  
not being in place.  
Water leaks at the elements may be due to:  
1. Defective elements which leak at terminals  
or through flange. Replace element*.  
2. Loose element/gasket leak:  
Tighten element with element wrench.  
If leak continues, remove element* and  
discard gasket. Clean gasket seating  
areas and reinstall element with new  
gasket.  
Condensation and dripping may appear on  
pipes when inlet water temperature is low.  
Pipe fitting may be leaking.  
Drain valve leakage could be from the valve itself. Either  
correct the problem or replace the valve*. To check for  
leakage where threaded portion enters tank, insert Q-tip  
or similar absorbent material between jacket opening  
and valve to swab spud area. Remove valve* if leak is  
indicated and repair with pipe joint compound.  
All water which appears at the heater bottom or on the  
surrounding floor may be caused by condensation, loose  
connections or relief valve operation and leakage. Do not  
replace the heater until a full inspection of all potential leak  
points is made and corrective steps taken to stop the leak.  
Leakage from other appliances, water lines, or ground seepage  
should also be suspected until proved otherwise.  
*
Contact a Qualified Service Agency as it is necessary to  
shut off electricity and drain tank to perform procedure.  
34  
pIpInG dIaGraMs  
one teMperature wIth cIrculatInG loop  
Insert B  
VacuuM relIef  
ValVe. Install per  
local codes.  
*pIpe to open draIn Install In  
accordance wIth all local  
codes.  
35  
pIpInG dIaGraMs  
Insert B  
VacuuM relIef  
ValVe. Install per  
local codes.  
36  
pIpInG dIaGraMs  
Insert B  
VacuuM relIef  
ValVe. Install per  
local codes.  
37  
pIpInG dIaGraMs  
one teMperature one heater VertIcal storaGe tank  
forced cIrculatIon wIthout BuIldInG recIrculatIon  
*pIpe to open draIn  
Install In accordance wIth all local codes  
two teMperature wIth MIXInG ValVe  
and cIrculatInG loop  
Insert B  
VacuuM relIef  
ValVe. Install per  
local codes.  
two teMperature wIth MIXInG ValVe  
38  
pIpInG dIaGraMs  
Insert B  
VacuuM relIef  
ValVe. Install per  
local codes.  
two heaters wIth horIZontal storaGe tank  
wIth or wIthout BuIldInG recIrculatIon  
39  
pIpInG dIaGraMs  
three heaters wIth VertIcal storaGe tank  
wIth or wIthout BuIldInG recIrculatIon  
Insert B  
VacuuM relIef  
ValVe. Install per  
local codes.  
three heaters wIth horIZontal  
storaGe tank wIth or wIthout BuIldInG  
recIrculatIon  
40  
pIpInG dIaGraMs  
four heaters wIth VertIcal storaGe tank  
wIth or wIthout BuIldInG recIrculatIon  
Insert B  
VacuuM relIef  
ValVe. Install per  
local codes.  
four heaters wIth horIZontal storaGe tank  
wIth or wIthout BuIldInG recIrculatIon  
41  
pIpInG dIaGraMs  
ManIfold kIts  
ALL DIMENSIONS IN INCHES  
ManIfold kIts  
two heaters  
tank capacity  
part  
(gallons)  
number  
h
w
d
a
52  
80  
9003429205 66 1/4  
9003429205 70 1/2  
9003429205 73 1/4  
56 3/4  
60 1/4  
64 1/2  
27 1/4 13 1/4  
31 1/4  
35 3/4  
9 3/4  
5 1/2  
120  
Inlet and outlet size - 1 1/2  
three heaters  
tank capacity  
part  
(gallons)  
number  
h
w
d
a
52  
80  
9003430205 66 1/4  
9003430205 70 1/2  
9003430205 73 1/4  
91 3/4  
95 1/4  
99 1/2  
27 1/4 13 1/4  
31 1/4  
35 3/4  
9 3/4  
5 1/2  
120  
Inlet and outlet size - 2 1/2  
four heaters  
tank capacity  
part  
(gallons)  
number  
h
w
d
a
52  
80  
9003431205 66 1/4 126 3/4 27 1/4 13 1/4  
9003431205 70 1/2 130 1/4 31 1/4  
9003431205 73 1/4 134 1/2 35 3/4  
9 3/4  
5 1/2  
120  
Inlet and outlet size - 2 1/2  
42  
warranty  
A. O. Smith Corporation, the warrantor, extends the following LIMITED WARRANTY to the owner of this water heater:  
1. THE TANK  
If the glass-lined tank in this water heater shall prove upon examination by the warrantor to have leaked due to natural corrosion from potable  
water therein, during the first THREE years after initial installation, the warrantor will supply a complete new A. O. Smith water heater of equivalent  
size and current model. Some government agencies are requiring energy efficient standards for water heaters. In the event regulations prohibit  
sale of a model of equivalent size and construction, A. O. Smith will provide a model which complies with the regulations of your area, in which  
case the consumer will be charged the difference in price between the like replacement and the energy efficient model required. The warranty on  
the replacement water heater will be limited to the unexpired term of the original warranty.  
2. ALL OTHER PARTS  
If within ONE year after initial installation of this water heater, any part or portion shall prove upon examination by the warrantor to be defective in  
material or workmanship, the warrantor will repair or replace such part or portion at its option.  
3. CONDITIONS and EXCEPTIONS  
This warranty shall apply only when the water heater is installed in accordance with local plumbing and building codes, ordinances and regulations,  
the printed instructions provided with it and good industry practices. In addition, a temperature and pressure relief valve, certified by A.G.A.and  
approved by the American Society of Mechanical Engineers, must have been installed.  
a. This warranty shall apply only when the heater is used:  
(1) at temperatures not exceeding the maximum setting of its thermostat;  
(2) at water pressure not exceeding the working pressure shown on the water heater;  
(3) when filled with potable water, free to circulate at all times;  
(4) in a noncorrosive and non-contaminated atmosphere;  
(5) in the United States, its territories or possessions, and Canada.  
(6) used with factory approved anode(s) installed;  
(7) in its original installation location;  
(8) sized in accordance with proper sizing techniques for commercial water heaters;  
(9) bearing a rating plate which has not been altered, defaced or removed except as required by the warrantor;  
(10) not used in a closed system without a properly sized and installed thermal expansion tank;  
(11) fired at the proper voltage and wattage;  
(12) maintained in accordance with the instructions printed in the manual included with the heater.  
b. Any accident to the water heater, any misuse, abuse (including freezing) or alteration of it, any operation of it in a modified  
form, or any attempt to repair tank leaks will void this warranty.  
4. SERVICE and REPAIR EXPENSE  
Under this limited warranty the warrantor will provide only a replacement water heater or part thereof. The owner is responsible for all other costs.  
Such costs may include but are not limited to:  
a. Labor charges for service, removal, repair, or reinstallation of the water heater or any component part;  
b. Shipping, delivery, handling, and administrative charges for forwarding the new heater or replacement part from the nearest  
distributor and returning the claimed defective heater or part to such distributor;  
c. All cost necessary or incidental for any materials and/or permits required for installation of the replacement heater or part.  
5. LIMITATIONS ON IMPLIED WARRANTIES  
Implied warranties, including any warranty of merchantability imposed on the sale of this heater under state law are limited to one (1) year duration for the  
heater or any of its parts. Some states do not allow limitations on how long an implied warranty lasts, so the above limitation may not apply to you.  
6. CLAIM PROCEDURE  
Any claim under this warranty should be initiated with the dealer who sold the heater, or with any other dealer handling the warrantor’s products.  
If this is not practicable, the owner should contact:  
U.S. Customers  
Canadian Customers  
A. O. Smith Water Products Company  
500 Tennessee Waltz Parkway  
Ashland City, TN 37015  
A. O. Smith Enterprises, Ltd.  
P. O. Box 310 - 768 Erie Street  
Stratford, Ontario N5A 6T3  
Telephone: 1-800-265-8520  
Telephone: 1-800-323-2636  
a. The warrantor will only honor replacement with identical or similar water heater or parts thereof which are manufactured or  
distributed by the warrantor.  
b. Dealer replacements are made subject to in-warranty validation by warrantor.  
7. DISCLAIMERS  
NO OTHER EXPRESS WARRANTY HAS BEEN OR WILL BE MADE IN BEHALF OF THE WARRANTOR WITH RESPECT TO THE  
MERCHANTABILITY OF THE HEATER OR THE INSTALLATION, OPERATION, REPAIR, OR REPLACEMENT OF THE HEATER. THE  
WARRANTOR SHALL NOT BE RESPONSIBLE FOR WATER DAMAGE, LOSS OF USE OF THE UNIT, INCONVENIENCE, LOSS OR DAMAGE  
TO PERSONAL PROPERTY, OR OTHER CONSEQUENTIAL DAMAGE. THE WARRANTOR SHALL NOT BE LIABLE BY VIRTUE OF THIS  
WARRANTY OR OTHERWISE FOR DAMAGE TO ANY PERSONS OR PROPERTY, WHETHER DIRECT OR INDIRECT, AND  
WHETHER ARISING IN CONTRACT OR IN TORT.  
a. Some states do not allow the exclusion or limitation of the incidental or consequential damage, so the above limitation or  
exclusion may not apply to you.  
b. This warranty gives you specific legal rights, and you may also have other rights which vary from state to state.  
Fill in the following for your own reference. Keep it. Registration is not a condition of warranty. The model and serial number are found on the heater’s rating plate.  
Model No.________________________________________ Serial No.________________________________ Date Installed ________________  
Dealer’s Name_________________________________________________________________________________________________________  
Dealer’s Address _______________________________________________________________________Phone No. _______________________  
City and State __________________________________________________________________________Zip ____________________________  
43  
500 Tennessee Waltz Parkway, Ashland City, TN 37015  
Technical Support: 800-527-1953 • Parts: 800-433-2545 • Fax: 800-644-9306  

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