AO Smith Water Heater BTI65G User Manual

MODELS  
BTI 65 G  
85 G  
100 G  
BTI  
BTI  
INSTALLATION AND USER  
INSTRUCTION  
UNITED KINGDOM / IRELAND  
HOTWATERSTORAGEHEATERS  
Read these installation instructions first before installing the appliance. Carefully read  
the user instructions before igniting the appliance. Failure to follow these instructions  
may lead to risk of explosion and/or fire and could cause material damage and/or bodily  
harm. Installation and commisioning should be carried out by a qualified competent  
installer. The type of gas and the value at which the appliance is set standard in the  
factory are registered on the rating plate. The appliance may only be installed in a room if  
this room meets the ventilation requirements.  
A.O.SMITHACCEPTSNORESPONSIBILITYFORWARRANTY,SERVICEAND/OR  
PRODUCTLIABILITYINCASEOFUNAUTHORISEDALTERATIONS,PRODUCT  
MODIFICATIONSORREPAIR.  
2
CONTENTS  
PAGE  
1.  
GENERAL  
1.1  
1.2  
Description ...................................................................................................... 4  
Technical safety equipment ............................................................................ 6  
Gas control valve............................................................................................ 6  
Control panel ................................................................................................... 6  
Operation of the storage water heater ........................................................... 7  
Combustion products discharge safety device ............................................. 7  
Technical information ...................................................................................... 8  
Dimensions ..................................................................................................... 8  
Technical data............................................................................................... 10  
1.2.1  
1.2.2  
1.2.3  
1.2.4  
1.3  
1.3.1  
1.3.2  
2.  
FORTHEINSTALLER  
2.1  
Installation instructions .................................................................................. 12  
Installation ..................................................................................................... 12  
Water circulation system .............................................................................. 13  
Gas connection............................................................................................. 15  
Flue system .................................................................................................. 15  
Flue down draught safety device ................................................................. 15  
Electrical connection ..................................................................................... 15  
Commissioning .............................................................................................. 16  
Filling the water heater ................................................................................. 16  
Putting in to operation.................................................................................... 16  
Shut down .................................................................................................... 16  
Removing and replacing the control panel front cover.................................. 17  
Setting the gas pressure .............................................................................. 17  
Removing and replacing the inner door ......................................................... 18  
Temperature regulation ................................................................................. 18  
Converting to another type of gas ................................................................ 19  
Maintenance ................................................................................................. 19  
Magenesium anode ....................................................................................... 19  
Cleaning ........................................................................................................ 20  
Decalcification............................................................................................... 20  
Spare parts ................................................................................................... 20  
Inletcombination............................................................................................ 20  
Gas smell ...................................................................................................... 20  
Condensation ................................................................................................ 20  
2.1.1  
2.1.2  
2.1.3  
2.1.4  
2.1.5  
2.1.6  
2.2  
2.2.1  
2.2.2  
2.2.3  
2.3  
2.4  
2.5  
2.6  
2.7  
2.8  
2.8.1  
2.8.2  
2.8.3  
2.8.4  
2.9  
2.10  
2.11  
3.  
FORTHEUSER  
3.1  
Commisioning ................................................................................................ 21  
Filling the water heater ................................................................................. 21  
Putting into operation..................................................................................... 21  
Use ............................................................................................................... 21  
Fault overview .............................................................................................. 22  
3.1.1  
3.1.2  
3.1.3  
3.2  
4.  
5.  
WARRANTY..................................................................................................... 23  
Appendix 1..................................................................................................... 25  
3
1. GENERAL  
1.1 Description of the  
appliance  
Construction of the water heater is in  
accordance with the European  
standard for gas heated water storage  
heaters for sanitary application (EN89).  
The appliance thus meets the European  
Directory for Gas Appliances and is  
therefore entitled to carry the CE-  
marking. It is an open flued appliance  
without ventilator and with a flue gas  
down draught safeguard, a Thermal  
Reflux Safeguard (TRS) (category  
B11BS). The water heater is suitable for a  
maximum working pressure of 8 bar.  
The water heater tank is manufactured  
from low carbon sheet steel and is  
glasslined on the inside. In addition the  
tank is fitted with a magenesium anode  
as extra protection against corrosion. A  
thick, CFC-free, PU insulation layer  
covered in a steel jacket reduces  
unnecessary heat loss. When the  
appliance is filled with water it  
continuously is under water pressure.  
As hot water is drained from the tank,  
cold water is added immediately. A flue  
baffle has been placed in the flue tube  
to improve heat tranfer. The flue gasses  
pass their heat on to the water by  
means of radiation and convection. The  
exhaust of the flue gasses is realized  
by natural thermal draught (see figur 1).  
Dead legs on a hot water installation are  
undesireable. Where possible they  
should be avoided. When the inclusion  
on the system of a dead leg is  
unavoidable the following restrictions  
should be applied:  
- for pipes not eceeding 19 mm. inside  
diameter; maximum length of dead leg  
permitted 12 metres;  
- for pipes exceeding19 mm. but not  
exceeding 25 mm. inside diameter;  
maximum lenght of dead leg 7,5  
metres;  
- for pipes with an inside diameter  
exceeding 25 mm. maximum length of  
dead leg 3 metres.  
4
Figur 1 - Cross section of the heater  
1)  
2)  
3)  
4)  
5)  
6)  
7)  
8)  
9)  
Draught diverter  
Hot water outlet  
Insulation  
10) Cold water inlet  
11) Combustion products discharge  
safety device  
12) T&P valve connection  
13) Outer casting  
Flue tube  
Glass lined tank  
Gas valve and spark ignition  
Control panel  
Inspection cover plate  
Intermittent pilot burner  
and flame probe  
14) Flue baffle  
15) Magnesium anode  
16) Drain valve and secondary  
return connection  
17) Main burner  
5
1.2 Technical safety  
equipment  
The automatic incandescent ignition (hot  
surface) ensures that the burner ignites  
as soon as there is a demand for heat.  
1.2.1 Gascontrolvalve  
The water heater is equipped with a  
gas control wich regulates the flow of  
gas to the burner. The gas block is  
equipped with a safety valve, gas valve  
and burner control (on a standard  
natural gas setting). To ensure  
improved ignition the gas control valve  
opening mechanism is fitted with a  
delay (softlite).  
The gas control block is suitable for  
gasses from the first, second and third  
gas family. The maximum inlet pressure  
is 60 mbar.  
1.2.2 Controlpanel  
Temperature control for the water  
heater is housed in the control panel  
(See figur 2). For safety purposes,  
heaters are always fitted with two  
thermostats: a control thermostat is  
adjustable between 40 °C and 80 °C  
and a safety thermostat 90 °C. The  
control panel is fitted with an ON/OFF  
switch (I/0). At setting ”I”, the gas  
control is activated on the basis of heat  
demand from the control thermostat. At  
setting ”0” the heater is switched off.  
Figur 2 - Top view of the heater  
A) Hot water outlet  
B) Cold water inlet  
1) Electrical connection  
2) ON/OFF switch  
3) Ignition controller reset button  
4) Control thermostat knob  
5) Safety thermostat reset button  
6
1.2.3 Operation of the storage  
water heater.  
operation by pressing its reset button. If  
this failure occurs frequently, this  
indicates that the flue suffers from down  
draught conditions. It is recommended  
that a competent person carry out the  
necessary remedial action.  
Normal operation  
When there is a demand for heat a  
waiting period of about 1 second  
elapses before the built-in spark gene-  
rator and pilot gas valve are switched  
on. The ignition sparks ignite the pilot  
burner and the resulting flame is  
detected by the ionisation electrode.  
Almost immediately after the pilot flame  
is detected, sparking stops and the  
main gas valve is openend. The main  
burner is lit by the pilot flame. The unit  
is now in operation. When the  
Important  
The combustion products  
discharge safety device should  
never be put out of operation. Re-  
entry of flue gases to the building  
could be harmful and cause  
poisoning or death.  
temperature of the water in the unit  
reaches the temperature that is set  
with the thermostat, the thermostat  
switches and disconnects the  
electrical heat demand signal to the  
burner controller. The gas valves are  
then closed.  
Ignition failure  
If the flame is not established within  
the safety period the automatic ignition  
controller locks out. The safety period  
is about 25 seconds. Lock-out is  
indicated by the lamp in the RESET-  
button on the control panel. The unit  
has to be manually reset by pushing  
the reset button. If the flame is lost  
during normal run, the automatic  
ignition controller repeats the start  
sequence.  
1.2.4 Combustionproducts  
discharge safety device  
The heater has been fitted with a  
combustion products discharge safety  
device. It is the function of the safety  
device to prevent flue gases from the  
water heater entering the room where  
the water heater has been placed,  
instead of passing through the flue to  
outside atmosphere. The gas supply is  
disconnected as soon as the device is  
activated by hot gases flowing over  
the sensor. After the cause of the re-  
entry of flue gases has been traced  
the device can be put back into  
7
1.3 Technical information  
1.3.1 Dimensions  
These water heaters are only suitable  
for a flue tube with minimal the  
announced diameter (dimension G).  
Dimensions  
BTI 65  
A
B
D
F
G
K
L
1680  
1510  
520  
655  
100  
340  
295  
M
N
P
Q
R
S
V
1
1540  
1540  
210  
535  
295  
1330  
205  
Cold water inlet  
Hot water outlet  
Gas control  
2
3
4
Drain valve  
5
T&P relief valve tapping  
Clean out  
6
All dimensions are given in mm. (rounded off on 5 mm). See figur 3.  
8
AOS 1092  
Figur 3 - Dimensions  
9
1.3.2 Technical data  
DESCRIPTION  
device category: II2H3+  
unit  
BTI 65  
DATA NATUREL GAS : G20 - 20 mbar  
Nominal capacity  
kW  
kW  
12.7  
18.1  
20  
Nominal load (gross)  
Supply pressure  
mbar  
mbar  
m3/h  
mm  
Burner pressure  
12.0  
1.7  
Gas consumption *  
Diameter main orifice  
Diameter pilot orifice  
Heating time DT= 45K  
DATA BUTANE : G30 - 30 mbar  
Nominal load (gross)  
Nominal capacity  
3.40  
mm 0.56 / 0.41  
min  
45  
kW  
kW  
17.2  
12.3  
30  
Supply pressure  
mbar  
mbar  
kg/h  
mm  
Burner pressure  
-
Gas consumption *  
Diameter main orifice  
Diameter pilot orifice  
DATA PROPANE : G31 - 37 mbar  
Nominal heat input (upper valvue)  
Output  
1.3  
1.90  
0.23  
mm  
kW  
kW  
16.4  
11.7  
37  
Inlet pressure  
mbar  
mbar  
kg/h  
mm  
Burner pressure  
-
Gas consumption *  
Diameter main orifice  
Diameter pilot orifice  
GENERAL  
1.2  
1.90  
0.23  
mm  
Storage capacity  
litres  
178  
3/4"-14NPT  
ISO7/1Rp1/2  
3/4"-14NPT  
3/4"-14NPT  
3/4"-14NPT  
8
Water connections**  
Gas connection  
-
-
Drain valve  
-
Anode  
-
T&Pplug  
-
Maximum operating pressure  
Empty weight  
bar  
kg  
88  
*
Gas consumption at 1013,25 mbar and 15 °C  
**  
For a leak proof sealed connection European coupling pieces can be used on the NPT  
connection nipples with a pipe thread of ISO 228/1  
10  
Electrical connection  
Electrical  
supply  
Frequency  
Electrically  
fused to  
220/240 V AC  
50 Hz  
5A  
Ionisation current.  
The minimal ionisation current is 0.9 mi-  
cro-Amperes DC. Below this current the  
burner controller will assume no flame  
present. When in normal operation, the  
ionisation current wil be about 1.2 to 1.3  
micro-Amperes DC when only the pilot  
flame is burning. (Adjust the main  
burner pressure to zero to be able to  
measure under this condition) With pilot-  
and main burner in operation, the  
ionisation current will be about 6.0 and  
6.3 micro-Amperes DC.  
Ionisation current can be measured by  
connecting a universal-meter in series  
in the connection to the ionisation  
electrode. Make sure to measure in Di-  
rect Current; Alternating Current in fact  
gives no information about the system’s  
behaviour.  
11  
2. FOR THE INSTALLER  
Fordomesticapplications:  
BS 5440 - part 1 and part 2.  
BS 5546 - Installation of gas hot water  
supplies for domestic  
2.1 Installationinstructions  
This water heater must be fitted in a  
location which will permit the provision  
os an approved flue system and ade-  
quate ventilation.  
purposes.  
BS 6700 - Specifications for design,  
installation and maintenance  
of services supplying water  
for domestic use within  
buildings and their  
curtilages.  
BS 6798 - Specification for installation  
of gas fired hot water  
boilers of rated input not  
exceeding 60 kW.  
BS 6891 - Specification for installation  
of low pressure gas  
A service clearance of 15 cm at the  
sides and rear of the unit and 60 cm at  
the front of the unit should be allowed  
for ease of servicing. Adequate  
distance must be allowed between the  
top of the unit and any obstruction or  
ceiling to allow the flue baffle and  
anode to be inspected, cleaned or in the  
case of the anode replaced if  
necessary.  
pipework of up to 28 mm in  
domestic premises.  
The water heater must stand on a level  
surface resistant to heat, insulted in  
accordance with local bylaws and Buil-  
ding Regulations 1985, with sufficient  
strength to support the weight of the  
unit when full of water.  
Fornon-domesticapplications:  
BS 5400 - part 1 and part 2.  
BS 6798 - Specification for installation  
of low pressure gas  
This water heater must not be installed  
in a bathroom, bedroom or in a cup-  
board opening on to such rooms. This  
water heater must not be installed in  
any area where flamable materials are  
used or stored.  
pipework of up to 28 mm in  
domestic premises.  
CP342 - Code of practice for  
centralised hot water  
supply part 2, buildings  
other than individual  
Insufficient ventilation may give rise to a  
risk of fire, explosion or suffocation. If  
in doubt consult the national and local  
regulations governing the installation of  
gas appliances or your British gas  
sevice department.  
dwellings and the following  
additional Codes of Practice.  
IM/2  
IM/5  
- Purging procedures for non-  
domestic gas installations.  
- Soundness testing  
procedures for industrial  
and commercial gas  
2.1.1 Installation  
installations.  
The installation of this water heater  
should be carried out by a suitably  
qualified competent person. It is a  
criminal offence for unqualified persons  
to install gas equipment.  
Installation should be carried out in  
accordance with all local authority and  
Building Regualions, Model Water  
Bylaws, bylaws of the local water  
supplier, Building Standards (Scotland)  
(Consolidation) Regulations and any re-  
levant requirements of the Local  
Authority, local gas regions and the  
following British Standards (current  
editions):  
IM/11  
IM/16  
- Flues for commercial and  
industrial gas fired boilers  
and air heaters.  
- Notes on installation of  
pipework (excluding 25 mm  
and below).  
Some chemicals produce vapours  
which can cause rapid failure of main-  
and pilotburners and storage tanks if  
they are drawn into the combustion air  
supply.  
12  
Therefore if this water heater will be  
used to supply hot water to:  
case appropriate valves and fittings  
should be used to ensure the system  
complies with the requirements of the  
water by laws, and appropriate building  
regulations.  
When fitting it is essential the rules of  
‘good practice’ are applied at all stages  
of installation.  
-
-
-
hairdressers,  
dry cleaners,  
industrial degreasing processes  
or any other area where  
compounds containing halogens are  
used and stored, care should be ta  
ken that all primary and secondary  
air is drawn from outside  
atmosphere free of such  
contaminents.  
Vented systems (See figur 4)  
If the water heater is to be connected to  
a cold feed tank or cistern the hot water  
supply pipe must include an open vent  
which discharges over the cold feed  
cistern. The cold feed cistern must have  
an actual capacity of greater volume  
than the hourly recovery rate of the  
water heater(s) which it supplies. The  
minimum actual capacity is 50 gallons or  
227 litres.  
For futher advise contact  
A.O. Smith.  
2.1.2 Water circulation system  
A.O. SMITH water heaters are suitable  
for connection to vented, unvented and  
pumped pressurised systems. In each  
1)  
2)  
3)  
4)  
5)  
6)  
7)  
A)  
B)  
C)  
D)  
E)  
Manual gas valve  
Stop valve  
Three way valve  
Safety valve  
Non return valve  
Circulationpump  
Drain valve  
Gas supply  
Hot water outlet  
Cold water inlet  
Overflow  
Return circulation loop  
AOS 1105  
Figur 4 - Connection diagram vented  
systems  
13  
Unvented system (See figur 5)  
To install an A.O. Smith water heater on  
an unvented cold water supply system  
a kit of valves and fittings fisted by the  
water reseach centre and complying  
with part G3 of the current building  
regulations should be used. Installation  
should be carried out generally as  
shown on the following diagram.  
AOS 1119  
Figur 5 - Connection diagram unvented  
systems  
1) Manual gas valve  
2) Stop valve  
A) Gas supply  
B) Hot water outlet  
C) Cold water inlet  
D) Hot water taps  
E) Return circulation  
3) Expansion vessel  
4) T&P safety valve  
5) Non return valve  
6) Circulationpump  
7) Drain valve  
8) Pressure reducing valve  
9) Expansion valve  
14  
2.1.3 Gasconnection  
Safeguard (TRS).  
The gas supply to this appliance must  
be installed in accordance with BS 6891  
(1988) and British Gas Publications UP1  
andUP2.  
Fit the 1/2” gas supply cock supplied  
with this unit immediately before the gas  
control. No heat or soldered joints  
should be applied in the vicinity of the  
gas control, as they could cause  
damage to the control. All connections  
and joints should be tested for gas  
soundness with a suitable leak detector  
(do not use a naked flame).  
This TRS can be recognized by the  
copper coloured spiral that is fitted to  
the lower edge of the draught diverter.  
The spiral is connected to a thermostat  
by means of a capillary tube. The wiring  
of the thermostat must be connected to  
the thermocouple circuit.  
Important  
The TRS should never be put out of  
operation. The reentry of flue  
gasses may cause poisoning.  
N.B. When operating this unit on LPG a  
suitable gas supply cock should be  
used.  
2.1.6 Electricalconnection  
All electrical connections must be  
carried out in accordance with IEE  
regulations by an accredited electrical  
installation company. The appliance  
must be connected to the mains by  
means of a permanent electrical  
connection. A main switch must be  
fitted in the phase between the perma-  
nent connection and the water heater.  
The feeder cable must have cores of at  
least 3 * 1.0 mm2 The connecting clamps  
for the electricity supply are indicated  
by the symbol for earth Á, N for neutral  
and L for live. Always check with a vol-  
tage tester if the live and the neutral  
have been connected correctly in the  
electricity supply. The electricity supply  
must comply with the requirements  
below:  
2.1.4 Flue system  
The water heater should be fitted with a  
flue system connected to the draught  
diverter. The flue pipe should rise for at  
least 50 cm. vertically before the  
inclusion of any bends. If a horizontal  
run of flue is required this should be  
kept to the minimum lenght possible and  
incorporate a rise of 6 cm. per metre of  
run. A split clip or flange should be  
provided in the flue close to the draught  
diverter for ease of servicing.  
All flue materials should be corrosion  
resident i.e. stainless steel or  
galvanised and must include a tested  
and apprved terminal to BS 5440 part 1.  
If the flue passes through any  
combustible marerial measures must be  
taken to protect against the possibility of  
fire.  
Electrical  
supply  
Frequency  
Electrically  
fused to a  
minimum of  
All flues must terminate in free air space  
approx. 1,5 metres from any vertical  
surface of structure i.e. chimney  
stacks, roof parapets, etc. If an existing  
chimney or flue is to be used this should  
be swept clean and be free of debris  
before an approved liner is installed and  
connected to the water heater.  
220/240 V AC  
50 Hz  
5A  
The maximum power consumption is  
25 W  
See electrical diagram for more  
information, appendix 1.  
2.1.5 Draughtdiverter  
The appliance has been fitted with a  
flue down draught safety device. The  
operation of the safeguard is based on  
the principle of the Thermal Reflux  
15  
2.2 Commissioning  
Note: If during normal use the reset  
button is pressed the gas valves will  
close and the automatic ignition  
controller will start a new sequence  
after releasing the reset button.  
2.2.1 Filling the water heater  
1. Close the drain tap.  
2. Open the cold water tap to the water  
heater and open all taps where hot  
water can be drained for de  
aeration. The water heater is filled  
as soon as cold water flows from all  
taps.  
2.2.3 Shutdown  
Note:The water heater should only be  
turned off when hot water will not be  
required for an extended period (e.g.  
holidays); otherwise it should be left on.  
To shut down put the ON/OFF switch  
into OFF position.  
3. Close all hot water taps.  
2.2.2 Puttingintooperation  
1. Check to see if the heater is filled  
with water by running a little to  
waste from a hot water tap  
connected to the heater.  
2. Check wether the ON/OFF switch is  
inOFF-position.  
3. Ensure gas supply is fully purged of  
air and turn on gas cock.  
4. Ensure that power has been  
correctly supplied to the unit. Use a  
voltage tester to check that the live is  
to “L” and neutral to “N”. (Flame  
detection is phase sensitive).  
5. When first starting, the controller can  
be in the lock out condition: depress  
the reset button to free the control.  
(After manual reset, an extended  
prepurge/waiting time will occur).  
6. Switch the ON/OFF switch into ON  
position. If the pilot fails to ignite  
within 25 seconds the controls will  
go to lock out and the reset button  
will need to be reset (wait 15  
seconds before attempting reset). It  
may be necessary to repeat the  
lighting sequence a number of times  
on the initial light up if all the air has  
not been purged from the gas  
supply.  
7. The main burner pressure has been  
factory set but should be checked  
once normal operation is established  
(see ‘Ratings’ for settings).  
8. Set the temperature regulator to the  
required setting (see  
‘Descalcification’).  
16  
2.3 Removing and  
2.4 Setting the gas pressure  
replacing the control  
panel front cover  
The gas pressure has been set to the  
correct values at the factory.  
Removing the cover (see figure 7)  
1. Remove the screw at the top centre of  
the control panel.  
2. Push the cover upwards until the  
hooks at the lower end clear the  
burner access opening and base tray.  
3. Pull the lower end of the cover slightly  
forward.  
Important: The following proce-  
dure must be followed when  
checking or setting the gas  
pressure:  
1. Shut down the heater by switching  
off the mains current (switch off  
main switch);  
4. Pull the cover down until the top edge  
is clear of the control panel and then  
remove.  
2. Connect a manometer to the  
pressure test nipple to measure the  
burner pressure on the gas control.  
3. Activate the heater and allow the  
burner to ignite;  
4. Check the burner pressure. If  
necessary, reset it by means of the  
burner pressure adjusting screw.  
Turning it anti-clockwise reduces  
burner pressure. Turning it  
clockwise increases burner  
pressure;  
Replacing the cover (see figure 7)  
1. Place the top of the cover inside the  
rim of the control panel and push it up  
as far as possible.  
2. Position the bottom hooks inside the  
burner access opening and over the  
rim of the base tray.  
3. Push the cover downwards until the  
lower hooks engage and the top  
screw holes align.  
5. Shut down the heater, remove the  
manometer and close the pressure  
nipple;  
4. Replace the screw in the top centre  
6. Restart the heater (test for  
soundness).  
of the cover.  
AOS 1130  
Figur 7 taking off and mounting the  
control panel  
17  
2.5  
Mountingtheinnerdoor  
2.6  
Temperature regulation  
Mode of operation: (see figur 8).  
1. Place the clips in the position on the  
inner door so the door can fullty stick  
into the opening.  
2. Lift the door up and rotate it over the  
burner into position.  
The appliance is under water supply  
pressure (maximum 8 bar). The amount  
of cold water that is added is equal to  
the amount of hot water used. The gas  
control block automatically regulates the  
gas supply. The main burner will ignite  
as soon as a reduction in water  
temperature is sended by the  
3. Pull the inner door against the inside  
of the skirt ring.  
thermostat. The main burner will shut  
down as soon as the preset  
4. Rotate the clips into postion with a  
tool.  
temperature is achieved.  
At high water temperatures there is  
more scale buildup in the appliance. It is  
for this reason that it is recommended to  
place the temperature control knob in  
position of  
60 °C as the accumulation of scale will  
be reduced.  
Figur 8 Removing and replacing the  
inner door.  
1) Burner bracket  
2) Inner door  
3) Clip  
5) Skirt ring  
6) Outer casting  
7) Base tray  
4) Mainburner  
18  
2.7 Converting to another  
type of gas  
2.8 Maintenance  
To ensure safe and efficient operation  
of the water heater it is recommended  
that it is cleaned and serviced at least  
once a year by a qualified competent  
person.  
For conversion of the appliance from  
natural gas to another type of gas, or  
visa versa, it is necessary to exchange  
the pilot injector and the main injector.  
The conversion may only be executed  
by a qualfied competent person.  
2.8.1 Magenesium anode  
The life cycle of the anode is  
determined by the quality and the  
quantity of the water flowing through  
the water heater. It is therefore  
recommended that the anode be  
inspected and replaced if necessary at  
least once a year.  
Procedure:  
1. Shut the heater down. Close the  
main inlet gas valve and switch off  
the electricity supply at the main  
switch;  
2. Remove the burner assembly;  
3. Replace the injectors with the cor-  
rect injectors from the conversion  
set. (see table below).  
1. Close the stop cock in the cold water  
supply pipe;  
2. Open the nearest hot water tap in  
order to allow the pressure to drop  
from the water heater and the pipes;  
3. Slacken the anode with a fitting  
wrench;  
4. Check the anode and replace it if it  
has been reduced in diameter by  
60% or more at any point on its  
lenght;  
Remark:  
-
When conversion of the appliance  
from natural gas to another type of  
gas, fix the screw on the gas block  
of the burner pressure control as  
far as the stop.  
5. Check for water leaks.  
-
When conversion of the appliance  
from another type of gas to natural  
gas, then the right burner pressure  
should be adjust.  
If is necessary to replace the anode it  
should be replaced by one of the same  
type. The type of anode required can be  
detemined on the basis of the type of  
the appliance and the serial number.  
unit  
BTI 65  
G20  
20  
G30  
30  
G31  
37  
Supply pressure  
Burner pressure  
mbar  
mbar 12.0  
3.40  
-
-
Diameter main injector mm  
1.90  
0.23  
1.90  
0.23  
Diameter pilot injector mm 0.56/  
0.41  
19  
2.8.2 Cleaning  
gas smell persists, alert the local gas  
company and/or your installer.  
1. Close the gas supply and demount  
the burner after it has cooled down  
2. Disconnect the burner assembly  
from the gas control  
3. Remove the complete burrner  
assembly  
4. Clean the burner with a soft brush  
5. Check the pilot burner and clean it if  
so required  
6. Check the combustion chamber, flue  
tube and flue baffle and clean these  
if required  
2.11 Condensation  
If the appliance is filled with cold water  
or if the hot water consumption is very  
high, condensation of flue gasses will  
occur on the cold surfaces of the  
combustion chamber and the flue tube.  
The water drops will fall on the burner  
and cause a sizzling noise. This is a  
normal phenomenon that will disappear  
as soon as the appliance reaches its  
normal operating temperature.  
After cleaning of the pilot- and main  
burner the operation of these should be  
checked. If necessary the burner  
pressure should be reset.  
Important warning  
The applicance should never be  
taken into operation with a closed  
cold water supply!  
Provision should always be made  
for expansion.  
2.8.3 Decalcification  
Formation of lime scale depends on the  
quality and quantity of the water used.  
In addition higher water temperatures  
lead to more deposit in the appliance. A  
temperature setting of 60° C is  
recommended in order to keep the  
calcification at a low level.  
Decalcification should be attempted with  
the proper means. For extensive  
information a decalcification instruction  
is available.  
2.8.4 Spare parts  
To be able to order spare parts it is im-  
portant to note the type of appliance as  
well as the serial number of the  
appliance. Based on this information the  
data concerning the spare parts can be  
determined.  
2.9 Inlet combination  
Not applicable in U.K. and Ireland.  
2.10 Gas smell  
Immediately shut the main gas tap. Do  
not light any fire or switch o any lights,  
do not use any electrical switches or  
alarm bells. Open windows. Thoroughly  
inspect all gas connections and, if the  
20  
3. FOR THE USER  
3.1 Commisioning  
8. Set the temperature regulator to the  
required setting (see ‘De-  
scalcification’).  
Warning  
3.1.3 Use  
Installing and commissioning of this wa-  
ter heater should only be carried out by  
a qualified competent heating engineer.  
The appliance is under water supply  
pressure (maximum 8 bar). The amount  
of cold water that is added is equal to  
the amount of hot water used. The gas  
control block automatically regulates the  
gas supply. The main burner will ignite  
as soon as a reduction in water  
temperature is sended by the  
thermostat. The main burner will shut  
down as soon as the preset  
temperature is achieved.  
At high water temperatures there is  
more scale buildup in the appliance. It is  
for this reason that it is recommended  
to place the temperature control knob in  
position of 60 °C as the accumulation of  
scale will be reduced.  
3.1.1 Filling the water heater  
1. Close the drain tap;  
2. Open the cold water tap to the water  
heater and open all taps where hot  
water can be drained for de  
aeration. The water heater is filled  
as soon as cold water flows from all  
taps;  
3. Close all hot water taps.  
3.1.2 Puttingintooperation  
1. Check to see if the heater is filled  
with water by running a little to  
waste from a hot water tap  
connected to the heater;  
2. Check wether the ON/OFF switch is  
inOFF-position;  
3. Ensure gas supply is fully purged of  
air and turn on gas cock;  
4. Ensure that power has been  
correctly supplied to the unit. Use a  
voltage tester to check that the live is  
to “L” and neutral to “N”. (Flame  
detection is phase sensitive);  
5. When first starting, the controller can  
be in the lock out condition: depress  
the reset button to free the control.  
(After manual reset, an extended  
prepurge/waiting time will occur);  
6. Switch the ON/OFF switch into ON  
position. If the pilot fails to ignite  
within 25 seconds the controls will  
go to lock out and the reset button  
will need to be reset (wait 15  
seconds before attempting reset). It  
may be necessary to repeat the  
lighting sequence a number of times  
on the initial light up if all the air has  
not been purged from the gas  
supply;  
7. The main burner pressure has been  
factory set but should be checked  
once normal operation is established  
(see ‘Ratings’ for settings);  
21  
3.2 Fault overview  
Failure  
Possible Cause  
Corrective Action  
Gas smell  
If you smell gas you should immediately  
close the main gas tap, you should not  
fight any fire or switch on light. electrical  
switches or bels. Open windows and  
immediately contact your installer or the  
local gas company  
Heater is  
off or  
Burner automat is in lock  
condition  
Reset burner automat with the RESET  
button on the top of the collumn  
does not  
ignit  
Blocked chimney  
Contact your installer to investigate the  
cause and rectify it  
Overheat thermostat is  
engaged  
Check control thermostat set at 60 °C.  
Allow the water to cooldown (open taps).  
Puts the RESET button at the panel. The  
heater should now operate. If it does not  
contact your installer.  
Gas supply shut off  
Open the inlet gas valve  
Insufficient Temperature set too low  
Set water temperature to higher valvue  
(60 °C recommended)  
hot water,  
or none  
at all  
Thermal Reflux Safeguard  
has shut down the heater  
After resetting the TRS activate the heater.  
If this occurs regularly, call your installer  
Overheat thermostat is  
engaged  
Allow the water to cool down (opentaps).  
Puth the RESET button at the panel.  
Supply of hot water exhausted  
Unindentifiable cause  
Reduce hot water use. Give the heater  
time to heat the water  
Switch off the elactricity to the heater, close  
the inlet gas valve and call your installer  
Explosive  
ignition  
Wrong inlet gas pressure and/or  
burner pressure  
Set the correct inlet pressure and/or burner  
pressure  
Dirty injectors  
Clean injectors  
Poor flame  
image  
Wrong inlet pressure and/or  
burner pressure  
Set the correct inlet pressure and/or burner  
pressure  
Water  
Condensation of (flue) gasses  
See chapter “Condensation”  
leakage  
Leakage from other water  
If possible trace the cause and/or call your  
installer  
heater or pipes in the vicinity  
22  
4. WARRANTY  
d) in a non corrosive atmosphere or  
area;  
The following conditions form the  
guarantee agreement between A.O.  
Smith Water Products Company (the  
warrantor) and the owner of the water  
heater.  
e) with an approved temperature and  
pressure relief valve of adequate  
capacity not exceeding the working  
pressure rating shown on the water  
heater, and installed in conformity  
with A.O. SMITH Water Products  
Companies installation instructions;  
f) when anode(s) have been inspected  
and renewed, if they are worn or  
erroded by 50% or more at any point  
of their length.  
4.1 Guarantee in general  
If within one year of the original  
installation date of the water heater any  
part or component other than the tank  
shall prove upon examination by the  
warrantor or authorised agent to be  
defective in material or workmanship,  
the warrantor will exchange such part  
or component.  
4.4 Exclusions  
The guarantee will be null and void:  
a) if the water heater has been  
damaged by an external cause;  
b) in case of misuse, neglect (including  
frost damage) or incorrect use of the  
water heater;  
4.2 Guarantee of the tank  
If within 3 years of the original  
installation date, the tank fails due to  
rust or corrosion from the water side,  
the warrantor will supply a complete  
new water heater of equivalent size  
and duty (excluding delivery and  
installation charges). On the replace-  
ment water heater a guarantee will be  
granted sufficient to cover the  
c) in case of unauthorised alteration,  
modification or repair;  
d) in case of ingress into the water  
heater of chemicals, pollutants or  
contaminants;  
e) if the hardness of the incoming wa-  
ter is, or has been, softened below  
60 ppm CaCO3;  
f) if the water heater is effected by  
corrosive vapours such as those  
found in hairdressers, dry cleaners  
and laundries or where some  
industrial degreasing products are  
used and stored (for further  
information and advise please con-  
tact the A.O. SMITH technical Depart-  
ment).  
ubexpired portion of the original 3 years  
guarantee of the originally installed wa-  
ter heater.  
4.3 Conditionsfor  
installation and use  
The guarantee applies to the heater only  
while it remains in its original location,  
and is installed in accordance with local  
plumbing and building regulations and all  
relevant Codes of Practice.  
4.5 Range of guarantee  
All replacement water heaters supplied  
under the terms of this warranty will be  
supplied ex stock on a F.O.B basis.  
A.O. SMITH accepts no responsability  
for carriage, labour or other installation  
costs.  
The water heater should alse have  
been used only:  
a) for potable water free to circulate at  
all times and with the tank free of  
damaging scale deposits;  
b) at temperatures not exceeding the  
maximum setting of its thermostat  
and ECO (Energy Cut Off device);  
c) At water pressures and/or energy  
inputs which do not exceed those  
stated on the rating plate of the wa-  
ter heater;  
23  
4.6 Claims  
Any claims under this warranty should  
be initiated with the dealer who  
originally sold the water heater or with  
any other dealer or stockist of the  
warrantors products.  
4.7 No other guarantee or  
warrantee either  
expressed or implied is  
made on behalf of A.O.  
SMITH Water Products  
Company  
With respect to the water heater in  
question further A.O. Smith does not  
guarantee this water heater as suitable  
for purpose except within the terms of  
warranty detailed above.  
A.O. SMITH Water Products Company  
will not be liable by virtue of this  
guarantee or otherwise for damage to  
any persons or property when arising  
out of contracts or tort.  
The terms of this guarantee do not ef-  
fect your statutory rights under United  
Kingdom Consumer Legislation.  
This guarantee applies to the following  
models:  
BTI 65 G  
BTI 85 G  
BTI 100 G  
APPENDIX 1 Connection diagram BTI models  
A = Ignition controller  
B = ON/OFF switch  
C = Pilot burner  
D = Spark electrode  
E = Flame probe  
M = Remotebutton  
1
2
3
4
5
6
= brown  
= blue  
= yellow/green  
= black  
= white  
= red  
N
P
R
S
T
= Terminalblock  
= Terminalblock  
= Earthterminals  
= Connector  
= Gas control valve  
= Terminalblock  
= Tank earth  
F
= Transformer flame detection *  
G = TRS  
H = Control thermostat  
K = Safety thermostat  
U
V
W = Casting earth  
L
= Timer*  
X
= Control panel base  
plate earth  
* = Optional  
26  
27  
0305 394 R3.1  

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