AO Smith Water Heater DEL User Manual

MODELS DEN AND DEL  
COMMERCIAL ELECTRIC WATER HEATERS  
Installation  
Operation  
Electrical  
Maintenance  
Wiring Diagrams  
Leakage Checkpoints Limited Warranty  
Replacement Parts  
A DIVISION OF A. O. SMITH CORPORATION  
McBee, South Carolina, USA  
CAUTION  
TEXT PRINTED OR OUTLINED IN RED CONTAINS INFORMATION RELATIVE TO YOUR SAFETY.  
PLEASE READ THOROUGHLY BEFORE INSTALLING AND USING THIS APPLIANCE.  
PLACETHESEINSTRUCTIONSADJACENTTOHEATERANDNOTIFYOWNERTOKEEPFORFUTUREREFERENCE.  
Printed in U.S.A. 0704  
PART NO. 195201-000  
ROUGH-IN DIMENSIONS  
* NO SIDE OUTLET AVAILABLE  
FOR DEL 6 MODELS  
ROUGH-IN DIMENSIONS  
Approx.  
Shipping Weight.  
Models  
Dimensions  
DEL-6  
No. of  
Elements  
Tank Capacity  
US Gals. Litres  
A
B
C
D
inches  
15 1/2  
18 1/4  
26  
22 1/4  
30 7/8  
32 1/4  
32 1/4  
34 1/2  
45 1/8  
54 7/8  
60 3/4  
59 3/8  
mm  
394  
464  
660  
565  
784  
819  
819  
876  
1146  
1394  
1543  
1508  
inches mm  
inches  
11  
12 1/2  
20 1/2  
15 3/8  
24 1/8  
25 9/16  
25 1/8  
mm  
279  
318  
521  
391  
613  
649  
638  
-
-
-
-
-
inches mm  
Lbs.  
35  
Kg.  
15.9  
24.5  
26.3  
33.1  
45.4  
56.7  
75.3  
44.5  
51.3  
59.4  
79.8  
95.7  
147.9  
1
1
1
1
2
2
2
1
2
2
2
2
2
6
10  
15  
20  
30  
40  
50  
30  
40  
50  
66  
80  
119  
23  
38  
57  
14 1/4  
18  
18  
362  
457  
457  
552  
552  
610  
673  
521  
521  
521  
552  
610  
746  
-
-
-
-
-
-
-
DEL-10  
DEL-15  
DEL-20  
DEL-30  
DEL-40  
54  
58  
73  
76  
21 3/4  
21 3/4  
24  
26 1/2  
20 1/2  
20 1/2  
20 1/2  
21 3/4  
24  
-
114  
151  
189  
114  
151  
189  
250  
303  
450  
8
8
8
8
8
8
8
8
8
203  
203  
203  
203  
203  
203  
203  
203  
203  
100  
125  
166  
98  
DEL-50  
DEN-30  
DEN-40  
DEN-52  
DEN-66  
DEN-80  
DEN-120  
-
-
-
-
-
-
113  
131  
176  
211  
326  
62 7/16 1586  
29 3/8  
-
RECOVERY CAPACITIES  
Element  
U.S. Gallons/Hr and Litres/Hr at TEMPERATURE RISE INDICATED  
Wattage  
INPUT  
KW  
F°  
C°  
36F°  
40F°  
54F°  
60F°  
72F°  
80F°  
90F°  
100F° 108F° 120F° 126F°  
55.5C° 60C° 66.6C° 70C°  
(Upper/Lower)  
20C° 22.2C° 30C° 33.3C° 40C° 44.4C° 50C°  
NON-SIMULATANEOUS OPERATION  
/1500  
GPH  
LPH  
GPH  
LPH  
GPH  
LPH  
GPH  
LPH  
GPH  
LPH  
GPH  
LPH  
GPH  
LPH  
GPH  
LPH  
17  
64  
23  
85  
28  
107  
34  
128  
45  
170  
51  
192  
56  
213  
68  
256  
15  
58  
20  
77  
25  
96  
30  
115  
41  
153  
46  
173  
51  
192  
61  
11  
43  
15  
57  
19  
71  
23  
85  
30  
114  
34  
128  
38  
142  
45  
10  
38  
14  
51  
17  
64  
20  
77  
27  
102  
30  
115  
34  
128  
41  
8
32  
11  
8
29  
10  
38  
13  
48  
15  
58  
20  
77  
23  
86  
25  
96  
30  
115  
7
26  
9
34  
11  
43  
14  
51  
18  
68  
20  
77  
23  
85  
27  
102  
6
23  
8
6
21  
8
28  
9
36  
11  
43  
15  
57  
17  
64  
19  
71  
23  
85  
5
19  
7
26  
8
32  
10  
38  
14  
51  
15  
58  
17  
64  
20  
77  
5
18  
6
24  
8
30  
10  
37  
13  
49  
14  
55  
16  
61  
19  
73  
1.5  
2.0  
2.5  
3.0  
4.0  
4.5  
5.0  
6.0  
/2000  
43  
14  
53  
17  
64  
23  
85  
25  
96  
28  
107  
34  
128  
31  
10  
38  
12  
46  
16  
61  
18  
69  
20  
77  
24  
92  
/2500  
3000/3000  
4000/4000  
4500/4500  
5000/5000  
6000/6000  
230  
170  
153  
SIMULATANEOUS OPERATION  
3000/3000  
4000/4000  
4500/4500  
5000/5000  
6000/6000  
GPH  
68  
256  
90  
341  
101  
384  
113  
426  
135  
511  
61  
230  
81  
307  
91  
345  
101  
384  
122  
460  
45  
170  
60  
227  
68  
256  
75  
284  
90  
341  
41  
153  
54  
205  
61  
230  
68  
256  
81  
307  
34  
128  
45  
170  
51  
192  
56  
213  
68  
256  
30  
115  
41  
153  
46  
173  
51  
192  
61  
230  
27  
102  
36  
136  
41  
153  
45  
170  
54  
205  
24  
92  
32  
123  
36  
138  
41  
153  
49  
23  
85  
30  
114  
34  
128  
38  
142  
45  
20  
77  
27  
102  
30  
115  
34  
128  
41  
19  
73  
26  
97  
29  
110  
32  
122  
39  
146  
6
8
LPH  
GPH  
LPH  
GPH  
LPH  
GPH  
LPH  
GPH  
LPH  
9
10  
12  
184  
170  
153  
Recovery capacities at 100° F rise equal: for non-simultaneous element operation = 4.1 gal. x KW of one element; for simultaneous element operation  
= 4.1 gal. x 2/3 KW of both elements. For other rises multiply element KW as previously explained by 410 and divide by temperature rise. Full load current for single  
phase = total watts : voltage.  
2
Do obtain new labels from A. O. Smith for placement on the  
blanket directly over the existing labels.  
FOREWORD  
Thank you for buying this energy efficient water heater from  
A.O. Smith Water Products Company. We appreciate your  
confidence in our products. 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.  
EXTENDED NON-USE PERIODS  
CAUTION  
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 a nearby 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 OPENED.  
In addition to these instructions, the equipment shall be installed  
in accordance with those installation regulations in force in the  
local area where the installation is to be made. Authorities having  
jurisdiction shall be consulted before installations are made.  
GENERAL SAFETY  
INSTRUCTIONS  
CAUTION  
AN ELECTRICAL GROUND IS REQUIRED TO REDUCE RISK  
OF ELECTRIC SHOCK OR POSSIBLE ELECTROCUTION. THE  
GROUND SCREW AT THE JUNCTION BOX IS FOR BONDING  
THE HEATER TO A GROUNDED SERVICE ENTRANCE  
CONDUCTOR, A GROUNDED SERVICE ENTRANCE RACEWAY,  
OR AN EARTH GROUNDING ELECTRODE CONDUCTOR.  
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.  
The principal components of the heater are identified on page 5.  
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.  
WARNING  
FAILURE TO FOLLOW THESE INSTRUCTIONS CAN RESULT  
IN SERIOUS PERSONAL INJURY OR DEATH.  
REQUIRED ABILITY  
WARNING  
INSTALLATION OR SERVICE OF THIS WATER HEATER  
REQUIRES ABILITY EQUIVALENT TO THAT OF A LICENSED  
TRADESMAN IN THE FIELD INVOLVED. PLUMBING AND  
ELECTRICAL WORK ARE REQUIRED.  
FOR CALIFORNIA INSTALLATION THIS WATER HEATER MUST  
BE BRACED, ANCHORED, OR STRAPPED TO AVOID FALLING  
OR MOVING DURING AN EARTHQUAKE. SEE INSTRUCTIONS  
FOR  
CORRECT  
INSTALLATION  
PROCEDURES.  
INSTRUCTIONS MAY BE OBTAINED FROM YOUR LOCAL  
DEALER, WHOLESALER, PUBLIC UTILITIES OR CALIFORNIA’S  
OFFICE OF STATE ARCHITECT, 400 P STREET, SACRAMENTO,  
CA 95814.  
GENERAL  
The installation must conform to these instructions, the local  
code authority having jurisdiction, and the requirements of the  
power company. In the absence of code requirements follow  
the latest edition of NFPA-70, The National Electrical Code which  
may be ordered from: National Fire Protection Association,  
1 Batterymarch Park, Quincy, MA 02269.  
INSULATION BLANKETS  
Insulation blankets available to the general public for external  
use on electric water heaters are not approved for use on your  
A.O. Smith water heater. The purpose of an insulation blanket is  
to reduce the standby heat loss encountered with storage tank  
water heaters. Your A. O. Smith water heater meets or exceeds  
the National Appliance Energy Act standards with respect to  
insulation and standby loss requirements, making an insulation  
blanket unnecessary.  
LOCATION  
The water heater should be located as close as possible to/or  
centralized to the water piping system. The water heater should  
be located in an area not subject to freezing temperatures.  
The heater should be located in an area where 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.  
WARNING  
Should you choose to apply an insulation blanket to this heater,  
you should follow these instructions (See page 5 for identification  
of components mentioned below). Failure to follow these  
instructions can result in fire, asphyxiation, serious personal  
injury or death.  
When such locations cannot be avoided, a suitable drain pan  
should be installed under the heater.  
Such pans should be at least two inches deep, have a minimum  
length and width of at least two inches greater than the diameter  
of the heater and should be piped to an adequate drain.  
Do not cover the temperature & pressure relief valve.  
Drain pans suitable for these heaters are available from your  
distributor or A. O. Smith Products Service Division,  
5621 W. 115th Street, Alsip, IL 60803.  
Do not cover the instruction manual. Keep it on the side of  
the water heater or nearby for future reference.  
3
CLEARANCES  
CALCULATING  
AMPERAGE/OVERCURRENT PROTECTION  
A minimum clearance of 4” must be allowed for access to  
replaceable parts such as the thermostats, drain valve and relief  
valve.  
The heaters come from the factory in two configurations:  
1. Two wire C-2 circuit for single element heater equipped with  
a high limit control, single phase power input.  
Adequate clearance for servicing this appliance should be  
considered before installation, such as changing the anodes,  
etc.  
2. Four wire A-8 circuit for dual element heater equipped with  
two high limit controls, single phase or three phase power  
input.  
FLOOD WARNING  
IF THE HEATER BECOMES IMMERSED IN WATER UP TO OR  
ABOVE THE LEVEL OF THE BOTTOM OF THE ELEMENT  
DOORS, THE HEATER SHOULD BE EXAMINED BY A  
COMPETENT SERVICE PERSON BEFORE IT IS PLACED IN  
OPERATION.  
The heater with dual elements is factory wired for connection to  
a three wire, three-phase delta branch circuit, non-simultaneous  
operation. In addition a ground conductor is required.  
Element connection is for non-simultaneous operation. This  
means only one element at a time operates. The wiring diagram  
(on page 5) shows the heater may be field converted to  
simultaneous element operation by moving the red wire on  
CHEMICAL VAPOR CORROSION  
Water heater corrosion and component failure can be caused by “J” terminal to L1. It is then possible for both elements to operate  
the heating and breakdown of airborne chemical vapors. Spray at once as determined by the thermostats. Regardless of  
can propellants, cleaning solvents, refrigerator and air element connection the heater operates in an “unbalanced”  
conditioning refrigerants, swimming pool chemicals, calcium fashion.  
and sodium chloride, waxes, and process chemicals are typical  
The heater may be field converted to single-phase operation by  
compounds which are potentially corrosive. These materials  
moving the wire on L3 of the terminal block to L2. L3 is not  
used. (See page 5).  
are corrosive at very low concentration levels with little or no odor  
to reveal their presence.  
The heater, now in single-phase non-simultaneous operation,  
Products of this sort should not be stored near the heater. Also,  
may be field-converted to single phase simultaneous operation  
air which is brought in contact with the water heater should not  
by moving the red wire on terminal “J” to L1, refer to wiring  
diagram on page 5.  
contain any of these chemicals. If necessary, uncontaminated  
air should be obtained from remote or outside sources.  
This is an example of calculating heater amperage for both  
types of element operation. From this, the branch circuit  
ELECTRICAL (GENERAL)  
conductor and overcurrent protection sizing can be established.  
Check the heater model and rating plate information against the  
characteristics of the branch circuit electrical supply. DO NOT  
CONNECT THE HEATER TO AN IMPROPER SOURCE OF  
ELECTRICITY. Contact the heater supplier for conversion  
information if necessary.  
The example is of a three-phase 240 volt unit with two, 6 kw  
elements. The notations are for units field converted to  
single-phase. Check the heater model and rating plate for actual  
specifications and substitute those values in the following.  
Voltage applied to the heater should not vary more than +5%  
to -10% of the model and rating plate marking for satisfactory  
operation.  
Non-simultaneous:  
(as factory wired)  
Simultaneous:  
(Field conversion)  
3000 : 240 = 12.5 amps*  
3000 : 240 = 12.5 amps*  
12.5 x 1.73 = 21.6 amps  
DO NOT ENERGIZE THE BRANCH CIRCUIT FOR ANY REASON  
BEFORE THE HEATER TANK IS FILLED WITH WATER. DOING  
SO WILL CAUSE THE HEATING ELEMENTS TO BURN OUT.  
*NOTE: as a single-phase  
non-simultaneous unit.  
*NOTE: as a single-phase  
simultaneous unit the  
total is:  
The factory wiring is attached to a terminal block within external  
junction box unit. The branch circuit is connected to terminal  
block within this junction box. The water heater should be  
connected to a separate, grounded, branch circuit with overcurrent  
protection and disconnect switch. The water heater should be  
grounded in accordance with national and local codes.  
12.5 x 2 = 25 amps  
The rating of the overcurrent protection should be computed on  
the basis of 125 percent 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.  
BRANCH CIRCUIT  
The branch circuit wire size should be established through  
reference to the latest edition of NFPA-70, the  
National Electrical Code or other locally approved source in  
conjunction with the heater amperage rating. For convenience,  
portions of the wire size tables from the Code are reproduced  
here. It is suggested the electrician size the branch circuit at 125  
Portion of Table 310-16 follows:  
Allowable Ampacities of Insulated Copper Conductors. Not  
more than three conductors in Raceway or Cable or Direct Burial  
(Based on Ambient Temperature of 30° C, 86° F).  
percent of the heater rating and further increase wire size as These ampacities relate only to conductors described in Table  
necessary to compensate for voltage drop in long runs.  
310-13 in Code.  
4
For ambient temperatures over 30° C (86° F), see Correction  
Factors, Note 13 in Code.  
Not more than three conductors in Raceway or Cable or Direct  
Burial (Based on Ambient Temperature of 30° C, 86° F. These  
ampacities relate only to conductors described in Table 310-13  
in Code.  
Size  
Temperature Rating of Conductor  
See Table 310-13 in Code  
For ambient temperatures over 30° C (86° F), see Correction  
Factors, Note 13 in Code.  
AMG  
MCM  
60° C  
75° C  
(167° F)  
TYPES:  
RH, RHW, RUH,  
(14-2), THW  
THWN, XHHW,  
(140° F)  
TYPES:  
RUW  
(14-2),  
T, TW,  
UF  
- - -  
- - -  
15  
Size  
Temperature Rating of Conductor  
See Table 310-13 in Code  
AMG  
MCM  
60° C  
(140° F)  
TYPES:  
RUW  
(12-2),  
T, TW,  
UF  
75° C  
(167° F)  
TYPES:  
RH, RHW, RUH,  
(12-2), THW  
THWN, XHHW,  
USE  
- - -  
- - -  
15  
20  
30  
45  
65  
85  
100  
18  
16  
14  
12  
10  
8
6
4
3
20  
30  
40  
55  
70  
80  
USE  
15  
25  
12  
10  
8
15  
25  
30  
40  
6
40  
50  
4
55  
65  
3
2
1
65  
75  
85  
75  
90  
100  
Portion of Table 310-18 follows:  
Allowable Ampacities of Insulated Aluminum and Copper -Clad  
Aluminum Conductors.  
WIRING DIAGRAMS  
A-8 CIRCUIT FOR DUAL ELEMENT HEATER  
C-2 CIRCUIT  
FOR SINGLE  
ELEMENT HEATERS  
EQUIPPED WITH HIGH  
LIMIT CONTROL  
FACTORY WIRED  
---------- FIELD WIRING  
WHITE FOR 120V  
5
TYPICAL PIPING CONNECTIONS  
This page shows typical water heater installations by model designations.  
DUAL ELEMENTS HEATER  
SINGLE ELEMENT HEATER  
INSTALL SUITABLE DRAIN PANS UNDER HEATERS TO  
PREVENT DAMAGE DUE TO LEAKAGE. REFER TO WATER  
HEATER LOCATION ON PAGE 2.  
INSTALL THERMAL  
EXPANSION TANK IF  
CHECK VALVE OR  
PRESSURE REDUCING  
VALVE IS USED IN  
SUPPLY LINE.  
INSTALL VACUUM RELIEF  
IN COLD WATER INLET  
LINE AS REQUIRED BY  
LOCAL CODES.  
† OVER CURRENT PROTECTION MUST BE SUPPLIED IN WATER HEATER CIRCUIT.  
CONSULT LOCAL CODE OR NEC-1984 FOR PROPER INSTALLATION.  
* INSTALL IN ACCORDANCE WITH ALL LOCAL CODES.  
that any discharge from the valve will exit only within 6 inches  
above, or at any distance below, the structural floor and cannot  
contact any live electrical part. THE DISCHARGE OPENING  
MUST NOT BE BLOCKED OR REDUCED IN SIZE UNDER ANY  
CIRCUMSTANCES.  
TEMPERATURE AND PRESSURE RELIEF VALVE  
CAUTION  
TO REDUCE THE RISK OF EXCESSIVE PRESSURES AND  
TEMPERATURES IN THIS WATER HEATER, INSTALL  
TEMPERATURE AND PRESSURE PROTECTIVE EQUIPMENT  
REQUIRED BY LOCAL CODES BUT NOT LESS THAN A  
COMBINATION TEMPERATURE AND PRESSURE RELIEF  
VALVE CERTIFIED BY A NATIONALLY RECOGNIZED TESTING  
LABORATORY THAT MAINTAINS PERIODIC INSPECTION OF  
PRODUCTION OF LISTED EQUIPMENT OR MATERIALS, AS  
MEETING THE REQUIREMENTS FOR RELIEF VALVE DEVICES  
FOR HOT WATER SUPPLY SYSTEMS. (ANSI Z21.22.)  
DUALELEMENT  
RATINGPLATE  
SINGLEELEMENT  
RATINGPLATE  
This valve must be marked with a maximum set pressure not to  
exceed the marked maximum working pressure of the water  
heater. Install the valve into an opening provided and marked for  
this purpose in the water heater, and orient it or provide tubing so  
6
Figure 3 shows the approximate time-to-burn relationship for  
normal adult skin. The thermostats on your water heater have a  
linear relationship between degrees of angular rotation and the  
corresponding change in temperature. Thus rotating the  
temperature adjustment indicator 30 angular degrees will result  
in a 10 degree Fahrenheit change in water temperature.  
OPERATION  
CAUTION  
DO NOT OPERATE THE HEATER WITHOUT INSTALLING AN  
APPROVED TEMPERATURE AND PRESSURE RELIEF VALVE  
IN THE OPENING PROVIDED IN THE TANK. GROUND THE  
HEATER TO GUARD AGAINST ELECTRIC SHOCK FROM THE  
HEATER OR WATER SYSTEM. NEVER OPERATE THE HEATER  
WITHOUT FILLING WITH WATER PER THE FILLING  
INSTRUCTIONS. FAILURE TO DO SO WILL DAMAGE INTERNAL  
PARTS.  
Temperature  
Setting  
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)  
125° F ( 52° C)  
120° F (49° C)  
Nearly instantaneous  
About 1/2 second  
About 1-1/2 seconds  
Less than 5 seconds  
About 30 seconds  
About 2 minutes  
FILLING  
1. Close the water heater drain valve by turning hand-wheel to  
right (clockwise).  
More than 5 minutes  
2. Open a nearby hot water faucet to permit the air in the system  
to escape.  
FIGURE3  
TEMPERATURE ADJUSTMENT  
3. Fully open the cold water inlet valve allowing the heater and  
piping to be filled.  
The water temperature is controlled by surface mounted  
thermostats with hi-limit. There is one mounted firmly against  
the tank directly above each element. The thermostats of A-8  
circuit are adjustable from approximately 120°F (49°C) (lowest  
setting) to 180°F (82°C) (highest setting). The thermostat of C-2  
circuit is adjustable from approximately 110°F (43°C) to 170°F  
(77°C) with a factory set point 120°F (49°C). The over temperature  
device (hi-limit) attached to each thermostat has a manual reset.  
4. Close the hot water faucet as water starts to flow.  
5. Turn on the electrical switch to the water heater.  
WARNING  
DO NOT ATTEMPT TO OPERATE HEATER WITH COLD WATER  
INLET VALVE CLOSED.  
TEMPERATURE REGULATION  
ADJUSTABLE UPPER  
THERMOSTAT BEHIND  
JUNCTION BOX DOOR  
ADJUSTABLE  
LOWER (SINGLE)  
THERMOSTAT  
DANGER  
THE WATER HEATER IS EQUIPPED WITH AN ADJUSTABLE  
THERMOSTAT TO CONTROL WATER TEMPERATURE. HOT  
WATER AT TEMPERATURES DESIRED FOR AUTOMATIC  
DISHWASHER AND LAUNDRY USE CAN CAUSE SCALDS  
RESULTING IN SERIOUS PERSONAL INJURY AND/OR DEATH.  
THE TEMPERATURE AT WHICH INJURY OCCURS VARIES WITH  
THE PERSON’S AGE AND TIME OF EXPOSURE. THE SLOWER  
RESPONSE TIME OF CHILDREN , AGED OR DISABLED  
PERSONS INCREASES THE HAZARD TO THEM. NEVER ALLOW  
SMALL CHILDREN TO USE A HOT WATER TAP, OR TO DRAW  
THEIR OWN BATH WATER. NEVER LEAVE A CHILD OR  
DISABLED PERSON UNATTENDED IN A BATHTUB OR  
SHOWER.  
FIGURE4  
NOTE: It is not necessary to adjust the upper thermostat for a  
dual element unit. However, if it is adjusted above the factory set  
point 140°F (60°C) it is recommended that it not be set higher  
than the lower thermostat setting.  
To change the temperature setting:  
DANGER  
1. Turn off the heater electrical supply. Do not attempt to adjust  
thermostat with power on.  
It is recommended that lower water temperatures be used to  
avoid the risk of scalding. It is further recommended, in all cases,  
that the water temperature thermostats (See Figure 3) be set for  
the lowest temperature which satisfies your hot water needs.  
This will also provide the most energy efficient operation of the  
water heater.  
2. Open the junction box door (for upper thermostat of dual  
element water heater only) and/or remove the (lower)  
thermostat access panel. Do not remove the plastic personel  
protectors covering the thermostats. The thermostat is factory  
pre-set at 140°F (60°C) for dual element units or at 120°F  
(49°C) for single element units.  
7
3. Using a flat tip screwdriver, rotate the adjusting knob to the Once a month the temperature and pressure relief valve should  
desired temperature setting.  
be checked to ensure that it is in operating condition. Lift the  
lever on the valve several times until the valve seats properly and  
operates freely.  
4. Replace the covers and access panels, and turn on heater  
electrical supply.  
CAUTION  
Valves for reducing point-of-use temperature by mixing cold and  
hot water are available (See Figure 5). Also available are  
inexpensive devices that attach to faucets to limit hot water  
temperatures. Contact a licensed plumber or the local plumbing  
authority.  
THE WATER PASSING OUT OF THE VALVE DURING THIS  
CHECKING OPERATION MAY BE EXTREMELY HOT.  
It is recommended that the drain valve on this unit be opened  
once a month and 1 to 2 gallons of water be allowed to drain out.  
A non-adjustable high temperature limit control operates before This will help to prevent sediment buildup in the tank bottom.  
steam temperatures are reached. The high limit is in the same  
area as the upper thermostat and must be reset manually when  
it operates. BECAUSE THE HIGH LIMIT OPERATES ONLY  
ANODE ROD MAINTENANCE  
WHEN ABNORMALLY HIGH WATER TEMPERATURES ARE  
The anode rod is used to protect the tank from corrosion. Most  
PRESENT, IT IS IMPORTANT THAT A QUALIFIED SERVICE  
hot water tanks are equipped with an anode rod. The submerged  
AGENT BE CONTACTED TO DETERMINE THE REASON FOR  
rod sacrifices itself to protect the tank. Instead of corroding the  
OPERATION BEFORE RESETTING.  
tank, water ions attack and eat away the anode rod. This does  
not affect the water's taste or color. The rod must be maintained  
to keep the tank in operating condition. Failure to inspect and/or  
replace the anode rod will result in voiding the warranty.  
Anode deterioration depends on water conductivity, not  
necessarily water condition. It may be necessary to have the  
anode rod inspected a few times during the first year to see what  
effect the water has had. A corroded or pitted anode rod, in the  
first year, indicates high water conductivity and should be checked  
and or replaced more often than an anode rod that appears to  
be fairly clean. Inspection should be conducted by a qualified  
technician.  
REPLACEMENT PARTS  
FIGURE5  
Replacement parts may be ordered through dealers, authorized  
DRAINING  
servicers or distributors. Refer to Yellow Pages for where to call  
or contact the Product Service Division, 5621 W. 115th Street,  
Alsip, IL 60803, 1-800-433-2545. When ordering parts, specify  
complete model number, serial number, (see rating plate),  
quantity and name of part desired. Standard hardware items  
should be purchased locally.  
If the heater is to be shut down and exposed to freezing  
temperatures, it must be drained. Water, if left in the tank and  
allowed to freeze, will expand and damage the heater.  
1. Turn off the electrical switch and cold water inlet valve.  
If desired, a hose may be connected to the drain valve  
to carry the water away.  
TROUBLESHOOTING  
2. Open a nearby hot water faucet and the heater drain  
valve.  
CHECKLIST  
Before contacting your dealer, check the water heater to see if  
the apparent malfunction is caused by some external fault.  
Consulting this checklist may eliminate the need for a repair call  
and restore hot water service.  
Be careful to grasp the drain valve handle in such a  
way that the hand will not be exposed to hot water.  
3. The drain valve must be left open during the shutdown  
period.  
NOT ENOUGH OR NO HOT WATER  
To restart heater, refer to the foregoing FILLING  
instructions.  
1. Be certain that the water heater electrical switch is turned to  
the ON position.  
MAINTENANCE  
In some areas an additional special meter, controlled  
by a timer, is used to govern the periods electricity is  
available. If the heater operates on a timed electrical  
circuit, recovery will be limited to certain hours.  
Electric water heater maintenance consists of cleaning the tank  
and removing lime (or scale) from the heating elements in hard  
water areas. Tank flushing should be performed monthly. Tank  
sediment removal and element lime scale removal must be  
performed when needed as determined by periodic inspections.  
Your dealer should be contacted for element cleaning. In some  
instances a hissing sound may be heard as the scale builds up.  
This noise is normal.  
2. Check for loose or blown fuses in the water heater circuit.  
3. If the water has been excessively hot and is now cold, the high  
temperature limit control may have operated. To restore  
8
service, contact your dealer or utility company. Refer to  
TEMPERATURE REGULATION section.  
Excessive water temperature.  
Faulty relief valve.  
4. The storage capacity of the heater may have been exceeded  
by large demands of hot water.  
Excessive water pressure is the most common cause of relief  
valve leakage. It is often caused by a “closed system”. A check  
5. If the heater was installed when incoming water temperatures valve in the inlet system will not permit the expanded hot water  
were warm, colder incoming temperatures will create the volume to equalize pressure with the main. A relief valve must  
effect of less hot water.  
release this water or the water heater or plumbing system will  
be damaged.  
6. Look for leaking or open hot water faucets.  
WATER IS TOO HOT  
When such a condition is encountered, local codes or inspection  
agency should be consulted to determine which system is  
acceptable in your area. These may consist of:  
Installation of a second relief valve with lower setting  
than the primary safety relief valve.  
1. Refer to TEMPERATURE REGULATION section.  
WATER HEATER MAKES SOUNDS  
1. See MAINTENANCE  
An expansion tank of suitable pressure and provision  
to avoid water logging.  
Removal of the check valve.  
WATER LEAKAGE IS SUSPECTED  
1. Check to see if the heater drain valve is tightly closed.  
IF YOU CANNOT IDENTIFY OR CORRECT  
THE SOURCE OF THE MALFUNCTION  
2. The apparent leakage may be condensation which forms on  
cool surfaces of the heater and piping.  
1. Place the water heater electrical switch in the OFF position.  
2. Close the cold water inlet valve to the heater.  
3. Contact your dealer.  
3. If the outlet of the relief valve is leaking it may represent:  
Excessive water pressure.  
NOTES  
9
LEAKAGE CHECKPOINTS  
Instructions: Use this illustration as a guide when checking for sources of water leakage. You or your dealer may be able to correct what  
appears to be a problem. NOTE: Cover and Insulation shown removed to reveal tank top  
Relief Valve  
Where possible remove or lift top cover to  
examine threads of fittings installed into tank  
for evidence of leakage. Correct fitting leaks  
as necessary.  
To Open Drain  
Condensation and dripping may appear on  
pipes when cold water temperature is low.  
Pipe fitting may be leaking.  
Water leaks at the elements may be due to:  
1. Defective element which leaks at terminals  
or thru flange. Replace element*.  
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  
material between jacket opening and swab  
spud area, remove valve* if indicated and  
repair with pipe joint compound.  
Anode Rod (Some Models)  
2. Loose element/gasket leak:  
(a)  
1-1/2” socket wrench or Part Number 23985  
wrench. If leak continues, remove  
element*, discard gasket and clean thread  
areas.Apply nonhardeningPermatex  
Screw-in type: tighten with  
Number 2 to thread areas, install new  
gasket and screw element into fitting until  
it seats. Tighten 1/2 to 3/4 turn with wrench.  
To Open Drain  
(b) Flange type: tighten screw with wrench.  
If leak continues remove element* and  
discard gasket. Clean gasket seating  
areas and re-install element with new  
gasket. NOTE: Part Number 40000-1 scale  
cleaning replacement screws available  
where threads have become rusted or  
damaged, preventing tightening.  
Water on the side of the tank may be  
condensation due to the panel or insulation  
not being in place.  
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 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 proven  
otherwise.  
Drain valve leakage could be from the valve  
itself.* 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.  
*Contact your dealer as it is necessary to shut off  
electricity and drain tank to perform procedure.  
10  
MODELS DEN AND DEL ELECTRIC WATER HEATER LIMITED WARRANTY  
A. 0. Smith Corporation, the warrantor, extends the following LIMITED WARRANTY to the owner of this water heater:  
1. THE TANK  
If the glass-Iined 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. 0. 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. 0. 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:  
(1) used at temperatures not exceeding the maximum calibrated setting of its thermostat;  
(2) used at water pressure not exceeding the working pressure shown on the heater;  
(3) filled with potable water, free to circulate at all times and with the tank free of damaging water sediment or scale deposits;  
(4) used in a non-corrosive and non-contaminated atmosphere;  
(5) used with factory approved anode(s) installed;  
(6) in its original installation location;  
(7) in the United States, its territories or possessions, and Canada;  
(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) used in an open system or in a closed system with properly sized and installed thermal expansion tank;  
(11) fired at the proper voltage and wattage as stated on the rating plate;  
(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. 0. Smith Water Products Company  
5621 W 115th Street  
Alsip, IL 60803  
A. 0. Smith Enterprises, Ltd.  
P. 0. 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 manufacture  
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  
City and State  
Phone No.  
Zip  
11  
5621 W. 115TH STREET, ALSIP, IL 60803  
Phone: 800-433-2545 Fax: 800-433-2515  
12  

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