American Water Heater 80 Thermal Efficiency UltraLow NOx Heavy Duty Commercial Gas Water Heater BCL3 User Manual

							21
WATER HEATER INSTALLATION
T&P VALVE DISCHARGE PIPE
Explosion Hazard
Temperature-Pressure Relief  Valve
must comply with  ANSI Z21.22-
CSA 4.4 and  ASME code.
Properly sized temperature-
pressure relief valve must be
installed in opening provided.
Can result in overheating and
excessive tank pressure .
Can cause serious injury or death.
This  water  heater  is  provided  with  a  properly  rated/sized  and 
certified combination temperature - pressure (T&P) relief valve by 
the manufacturer. See Temperature-Pressure Relief Valve on pages 
13-14 for information on replacement and other requirements.
Water Damage Hazard
Temperature-Pressure Relief V alve discharge
pipe must terminate at adequate drain.
CAUTION
Install a discharge pipe between the T&P valve discharge opening 
and  a  suitable  floor  drain.  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.
T&P Valve Discharge Pipe Requirements: •  Shall not be smaller in size than the outlet pipe size of the 
valve, or have any reducing couplings or other restrictions.
•  Shall not be plugged or blocked.
•  Shall not be exposed to freezing temperatures.
•  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.
•  Must terminate a maximum of six inches above a floor 
drain or external to the building. In cold climates, it is 
recommended that the discharge pipe be terminated at an 
adequate drain inside the building.
•  Shall not have any valve or other obstruction between the 
relief valve and the drain.
WATER LINE CONNECTIONS
The water piping installation must conform to these instructions 
and to all local code authority having jurisdiction. Good practice 
requires that all heavy piping be supported.
Read  and  observe  all  requirements  in  the  following  sections 
before installation of the water piping begins:
1.  Water Temperature Control and Mixing Valves on page 12.
2.  Dishwashing Machines on page 13.
3.  Temperature-Pressure Relief Valve on page 13.
4.   Closed Systems and Thermal Expansion on page 13.
5.  For  multiple  water  heater  installations  see  Water  Piping 
Diagrams beginning on page 35.
Water (potable) Heating And Space Heating
1.   All  piping  components  connected  to  this  unit  for  space 
heating  applications  shall  be  suitable  for  use  with  potable 
water.
2.  Toxic  chemicals,  such  as  those  used  for  boiler  treatment, 
shall NEVER be introduced into this system.
3.  This unit may NEVER be connected to any existing heating 
system or component(s) previously used with a non-potable 
water heating appliance.
4.   When  the  system  requires  water  for  space  heating  at 
temperatures  higher  than  required  for  domestic  water 
purposes,  a  tempering  valve  must  be  installed.    Please 
refer to Water Piping Diagrams beginning on page 35 of 
this manual for suggested piping arrangements.
5.  These  water  heaters  cannot  be  used  in  space  heating 
applications only
Thermometers (not Supplied)
Thermometers should be obtained and field installed as shown 
in the installation diagrams.
Thermometers  are  installed  in  the  system  as  a  means  of 
detecting the temperature of the outlet water supply.
Water Piping Diagrams
This manual provides detailed water piping diagrams for typical 
methods  of  application  for  the  water  heaters,  see  Water  Piping 
Diagrams beginning on page 35.
The  water  heater  may  be  installed  by  itself,  or  with  a  separate 
storage  tank.  When  used  with  a  separate  storage  tank,  the 
circulation  may  be  either  by  gravity  or  by  means  of  circulating 
pump. Adjust flow by throttling a full port ball valve installed in the 
circulating line on the outlet side of the pump. Never throttle flow 
on the suction side of a pump. See the Water Piping Diagrams 
beginning on page 35.
NOTE:  In addition to the factory installed Temperature-Pressure 
Relief  Valve  (T&P  valve)  on  the  water  heater,  each  remote 
storage tank that may be installed and piped to a water heating 
appliance  must  also  have  its  own  properly  sized,  rated  and 
approved Temperature-Pressure Relief Valve installed. 
Call  the  toll  free  technical  support  phone  number  listed  on  the 
back cover of this manual for further assistance in sizing a T&P 
valve for remote storage tanks.  
						

							22
INSTALLATION DIAGRAMS - TOP INLET/OUTLET USAGE
Use  of  the  top  inlet  water  connection  requires  an  inlet  dip  tube 
(refer  to  figure  19).  The  tube  is  supplied  in  the  heater.  Follow 
caution  labels  if  applying  heat  to  this  fitting.  Do  not  allow  pipe 
dope to contact the plastic tube during installation.TUBE INLET INSTALLATION
FIGURE 19.  
						

							23
HEATER WIRING
ELECTRICAL WIRING
All electrical work must be installed in accordance with the National Electrical Code, ANSI/NFPA 70 or the Canadian Electrical Code, 
CSA C22.1 and local requirements. When installed, the water heater must be electrically grounded in accordance with local codes or, 
in the absence of local codes, with the National Electrical Code, ANSI/NFPA 70 or the Canadian Electrical Code, CSA C22.1. If any 
of the original wire as supplied with the water heater must be replaced, it must be replaced with 105°C rated wiring or its equivalent, 
except in the burner housing. In this case 200°C rated wire must be used.
The controls of this water heater are polarity sensitive. Be certain to properly wire the hot and neutral connections.
24V
24V(GND)GNDPVMV/PVMV
SPARK
4
2
BK
BKR R R
R
LOWER PROBEUPPER PROBE
THERMOSTAT
BLOWER
PRESSURE
SWITCH
1a1b1
120 VAC HOT120 VAC NUETRAL
EARTH GROUND
PILOT
IGNITION MODULE
GAS VALVE
BLOWER
FACTORY INSTALLE DBY INSTALLER
POWER RELAY
IF ANY OF THE ORIGINAL WIRE AS SUPPLIED MUST BE REPLACED US ONLY 18 AWG \
105C 600V UL AWM STYLE #1015 WIRE EXCEPT GAS VALVE CABLE WHICH MUST USE 2 CONDUCTOR 18 AWG 80C 300V UL CATEGORY QPTZ POWER LIMITED CIRCUIT CABL E327382-000 REV. 00
R
R
R
BLK
W
WBLK
W
LEGEND:R= REDW= WHITEBLK= BLACKY= YELLOWY
MP
BLUE
BLK
LOW GASPRESSURESWITCH(SELECT MODELS)
FIGURE 20.
WIRING DIAGRAM  
						

							24
GAS PIPING
Contact  your  local  gas  service  company  to  ensure  that  adequate 
gas  service  is  available  and  to  review  applicable  installation  codes 
for your area.
Size the main gas line in accordance with Table 7. The figures shown 
are for straight lengths of pipe at 0.5 in. W.C. pressure drop, which is 
considered normal for low pressure systems. Note: Fittings such as 
elbows,  tees  and  line  regulators  will  add  to  the  pipe  pressure  drop. 
Also refer to the current edition of the National Fuel Gas Code.
Schedule  40  Steel  or  Wrought  Iron  Pipe  is  the  preferred  material 
for  the  gas  line  of  this  water  heater.  It  is  imperative  to  follow  the 
sizing  recommendations  in  the  current  edition  of  the  National  Fuel 
Gas  Code  if  Corrugated  Stainless  Steel  Tubing  (CSST)  is  used  as 
the gas line for this water heater.
The  heater  is  not  intended  for  operation  at  higher  than  14.0"  W.C.- 
natural gas, (1/2 pound per square inch gage) supply gas pressure. 
Exposure  to  higher  supply  pressure  may  cause  damage  to  the  gas 
control  valve  which  could  result  in  fire  or  explosion.  If  overpressure 
has  occurred  such  as  through  improper  testing  of  gas  lines  or 
emergency  malfunction  of  the  supply  system,  the  gas  control  valve 
must be checked for safe operation. Make sure that the outside vents 
on  the  supply  regulators  and  the  safety  vent  valves  are  protected 
against blockage. These are parts of the gas supply system, not the 
heater. Vent blockage may occur during ice storms.
TABLE 7 - GAS SUPPLY PIPE LENGTHS (IN FEET)
Maximum Equivalent Pipe Length - Natural Gas Only
Input rate 
(BTU/HR) Schedule 40 Steel or Wrought Iron Pipe
1/2" 3/4" 1"1 1/4" 1 1/2"
120,000 2070200 200200
154,000 1040150 200200
180,000 -30 100 200200
199,000 -30 90200 200
250,000 -20 60200 200
275,000 -10 50200 200
310,000 -10 40150 200
366,000 --30 100 200
390,000 --20 100 200
Fitting Type* Equivalent length in feet
45°Ell 0.71.01.21.61.9
90°Ell 1.62.12.63.54.0
Te e 3.14.15.26.98.0
Natural Gas 0.60 Specific Gravity, 0.50" W.C. Pressure Drop
*Screwed Fittings
It  is  important  to  guard  against  gas  control  valve  fouling  from 
contaminants  in  the  gas  ways.  Such  fouling  may  cause  improper 
operation, fire or explosion.
If  copper  supply  lines  are  used  they  must  be  internally  tinned  and 
certified  for  gas  service.  Before  attaching  the  gas  line,  be  sure  that 
all gas pipe is clean on the inside.
To trap any dirt or foreign material in the gas supply line, a sediment 
trap must be incorporated in the piping (see Figure 21). The sediment 
trap must be readily accessible and not subject to freezing conditions. 
Install in accordance with recommendations of serving gas suppliers. 
Refer to the current edition of the National Fuel Gas Code.
To prevent damage, care must be taken not to apply too much torque 
when attaching gas supply pipe to gas control valve inlet.
Apply  joint  compounds  (pipe  dope)  sparingly  and  only  to  the  male 
threads of pipe joints. Do not apply compounds to the first two threads. 
Use compounds resistant to the action of liquefied petroleum gases.
Gas Meter Size – Natural Gases Only
Be sure the gas meter has sufficient capacity to supply the full rated 
gas input of the water heater as well as the requirements of all other 
gas fired equipment supplied by the meter. If gas meter is too small, 
ask  the  gas  company  to  install  a  larger  meter  having  adequate 
capacity.
GAS PIPING AND SEDIMENT TRAP INSTALLATION
FIGURE 21.
GAS LINE LEAK TESTING
Fire and Explosion Hazard
Leak test before placing the water
heater in operation.
Disconnect gas piping and main gas
shutof f valve before leak testing.
Install sediment trap in accordance
with NFP A 54.
Use joint compound or 
Teflon tape
compatible with propane gas.
Any time work is done on the gas supply system perform a leak test 
to avoid the possibility of fire or explosion.
1.  For  test  pressures  exceeding  1/2  psi  (3.45  kPa)  disconnect  the 
water heater and its Main Gas Shutoff Valve from the gas supply 
piping  system  during  testing,  see  Figure  21.  The  gas  supply  line 
must be capped when disconnected from the water heater.
2.  For  test  pressures  of  1/2  psi  (3.45  kpa)  or  less,  the  water  heater 
need  not  be  disconnected,  but  must  be  isolated  from  the  supply 
gas line by closing the Main Gas Shutoff Valve during testing.
3.  Coat  all  supply  gas  line  joints  and  connections  upstream  of    the 
water  heater  with  a  non-corrosive  soap  and  water  solution  to 
test  for  leaks.  Bubbles  indicate  a  gas  leak.  Do  not  use  matches, 
candles, flame or other sources of ignition for this purpose.
4.  Repair any leaks before placing the water heater in operation.
PURGING
Gas line purging is required with new piping or systems in which air 
has entered.
Purging should be performed per the current edition of NFPA 54 the 
National Fuel Gas Code.  
						

							25
PRIOR TO START UP
Installation  and  start  up  of  this  water  heater  requires  abilities 
and  skills  equivalent  to  that  of  a  licensed  tradesman  in  the  field 
involved, see Qualifications on page 6.
Do  not  place  the  water  heater  in  operation  if  any  part  has  been 
under  water.  Immediately  call  a  qualified  service  technician  to 
inspect  the  water  heater  and  to  replace  any  part  of  the  control 
system and any gas control which has been under water. 
Light  the  water  heater  in  accordance  with  the  Lighting  and 
Operation Instruction label on the water heater and in this manual 
on page 27.
The  water  heaters  covered  by  this  manual  are  equipped  with 
an  electronic  control  system  that  automatically  sequences  the 
Blower,  the  Igniter,  the  24  VAC  Gas  Valve,  Burner  ignition, 
and  flame  sensing.  The  control  system  will  lock  out  after  three 
unsuccessful ignition attempts.
Before  attempting  start  up,  thoroughly  study  and  familiarize 
yourself  with  the  exact  Sequence  Of  Operation,  see  the  written 
Sequence  Of  Operation  on  page  27  and  the  Sequence  Of 
Operation Flow Chart on page 28.
Be certain that the water heater is full of water, that air is purged 
from  the  gas  and  water  lines  and  that  there  are  no  leaks  in  the 
gas and water lines. Ensure all inlet water valves are open.
Filling The Water Heater
Follow these steps to fill the water heater prior to start up.
1. Close the heater drain valve.
2.  Open a nearby hot water faucet to permit the air in the system 
to escape.
3.  Fully  open  the  cold  water  inlet  valve  allowing  the  piping  and 
water heater to fill with water.
4.  Close the hot water faucet opened in Step 2 as water starts to flow.
Supply Gas Line Purging
Fire or Explosion Hazar d
Read instruction manual before
installing, using or servicing water heate r.
To avoid risk of fire or explosion purge discharge must not
enter into confined areas or spaces where ignition can occur .
The area must be well ventilated and all sources of ignition
must be deactivated or removed.
Gas line purging is required with new piping or systems in
which air has entered.
Use only the gas shown on the water heater rating label.
Keep ignition sources away from faucets after extended
periods of non-use.
1. Close the Main Gas Shutoff Valve, see Figure 21 on page 24.
2.  Purge all air from the supply gas line up to the water heater’s 
Main Gas Shutoff Valve.
3.  When all air has been purged from the supply gas line, tighten 
all supply gas line connections. 
4.  Check  for  gas  leaks,  see  Gas  Line  Leak  Testing  on  page  24 
and repair any leaks found.
START UP
INITIAL START UP
Required Test Equipment
U-tube  manometer,  pressure  gauge,  or  digital  manometer. 
Recommended range: 20” W.C. (5 kPa).
NOTE:  All  test  equipment  must  be  acclimated  to  ambient 
temperature before calibration and use.
Preparation
1. Adjust the thermostat to the lowest temperature setting.
2.  Turn the water heater’s on/off switch to the “off” position.
3.  Close the Main Gas Shut Off Valve, see Figure 21 on page 24.
4.  Wait five (5) minutes for any residual gas to clear.
5.  Open  the  Supply  Gas  Pressure  Port  on  the  gas  control  valve 
by  turning  the  center  screw  counter-clockwise.  Connect  the 
manometer to the supply gas pressure test port, see Figure 22.
6.  Open the Main Gas Shutoff Valve.
7.  Measure  and  record  the  supply  gas  pressure,  this  is  a  “static” 
supply gas pressure reading; while the water heater is not firing.
FIGURE 22. – TOP VIEW
Lighting The Water Heater
1.  Turn the water heater’s on/off switch to the “on” position.
2.  Adjust the thermostat to the desired water temperature.
3.  Record the supply gas pressure when the 24 VAC Gas Valve is 
energized and the Burner is operating. This is a “dynamic” gas 
pressure reading; while the water heater is firing.
4.  Compare  the  actual  supply  gas  pressure  reading  recorded  
above to the required minimum/maximum values given in Table 
3 on page 8. Adjust supply gas pressure as necessary, see the 
instructions that follow.
5.  After the supply gas pressure adjustments are complete, turn off 
the water heater and close the Main Gas Supply Shut Off Valve. 
Disconnect the manometer from the Supply Gas Pressure Port 
and turn the center screw clockwise until the port is closed.
Supply Gas Pressure Adjustment
Fire and Explosion Hazar d
Turn of f gas lines during installation.
Contact a qualified installer or servic e
technician for installation and service.
Excessive gas pressure to gas valve ca n
cause serious injury or death. Do not use water heater with any gas
other than the gas shown on the rating
label.   
						

							26
7. If improper venting is observed during any of the above tests, 
the venting system must be corrected.
FAILURE TO CORRECT BACK DR AFTS MAY CAUSE AIR 
CONTAMINATION AND UNSAFE CONDITIONS.
•  If the back draft cannot be corrected by the normal method or 
if  a  suitable  draft  cannot  be  obtained,  a  blower  type  flue  gas 
exhauster  must  be  employed  to  ass ure  proper  venting  and 
correct combustion.
CHECKING THE INPUT
Follow these instructions to determine the firing rate of the water 
heater.
1.  Follow the procedure described in the "Initial Start Up" section 
on  page  25  to  measure  the  static  and  dynamic  supply  gas 
pressures.  Verify  that  the  static  and  dynamic  supply  gas 
pressures conform to the values listed in Table 3 on page 8.
2.  Use  this  formula  to  “clock”  the  meter.    Be  sure  that  other  gas 
consuming appliances are not operating during this interval.
  (3600/T) x H = Btuh
  T  =  Time in seconds to burn one cubic foot of gas.
  H = Btu’s per cubic foot of gas.
  Btuh = Actual heater input.
  Example: (BCL3100T1996NOX)
  T = 18.1 seconds
  H = 1000 BTU/Cu.Ft.
  Btuh = (3,600/18.1) x 1,000 = 199,000
  (Compare with BCL3100T1996NOX model and rating.)
UNDER NO CIRCUMSTANCES SHOULD THE GAS INPUT EXCEED  
THE  INPUT  SHOWN  ON  THE  HEATER'S  R ATING  PLATE.
WATER TEMPERATURE ADJUSTMENT
Wa ter temperature over 125°F (52°C)
can cause severe burns instantly
resulting in severe injury or death.
Children, the elderly and the
physically or mentally disabled are at
highest risk for scald injury .
Feel water before bathing or
showering.
Te mperature limiting devices such as
mixing valves must be installed
when required by codes and to
ensure safe temperatures at fixtures.
The  water  temperature  is  controlled  by  a  thermostat,  Fig.  3, 
which has two sensing elements. One sensor is located near the 
top of the tank and the other is near the center. The thermostat 
is set in the lowest position before the heater leaves the factory.
The  thermostat  temperature  dial,  Fig.  3,  is  accessible  by 
removing the control cover. The dial is adjustable and may be set 
for  120°F  (49°C)  to  180°F  (82°C)  water  temperature,  but  120°F 
(49°C) is the recommended starting point. It is suggested the dial 
be  placed  on  the  lowest  setting  which  produces  an  acceptable 
hot water supply. This will always give the most energy efficient 
operation. The temperature control has a 4°F fixed differential.
Supply  gas  pressure  shall  be  measured  while  the  water  heater 
is not firing (static pressure) and while the water heater is firing 
at full capacity (dynamic pressure). 
If  the  supply  gas  pressure  to  the  water  heater  is  not  between 
the  required  minimum  and  maximum  values  given  in  Table  3 
on page 8 adjust the supply gas regulator as necessary. Adjust 
the  supply  gas  regulator(s)  per  the  regulator  manufacturer’s 
instructions  to  achieve  the  required  “static”  and  “dynamic” 
supply gas pressure.
Multiple Water Heater Installations:
In  multiple  water  heater  installations  or  in  installations  where 
the  installed  water  heater(s)  share  a  common  gas  supply  main 
with  other  gas  fired  appliances;  the  supply  gas  pressures  shall 
be measured at each water heater with all gas fired appliances 
connected to a common main firing at full capacity.
On multiple water heater installations the supply gas line regulators 
shall  be  adjusted  to  provide  gas  pressure  to  each  water  heater 
within the minimum and maximum supply pressure requirements 
listed in Table 3 on page 8 with all gas fired appliances connected 
to a common gas main firing at full capacity.
NOTE:   A  pressure  drop  of  more  than  1.5”  W.  C.  (0.37  kPa) 
when the Main Burner ignites is an indication of an inadequate 
supply of gas and can lead to ignition failure, rough starts and/
or rough operation. If a drop of more than 1.5” W. C. (0.37 kPa) 
in  supply  gas  pressure  occurs  when  the  Main  Burner  ignites, 
ensure  the  supply  gas  lines  and  regulator(s)  are  properly  sized 
and  installed.  See  the  requirements  for  Supply  Gas  Regulator 
on page 12 and Gas Piping on page 24. Ensure all requirements 
and installation instructions are maintained.
CHECKING VENTING
The  following  steps  shall  be  followed  with  each  appliance 
connected to the venting system placed in operation, while any 
other  appliances  connected  to  the  venting  system  are  not  in 
operation.
1.  Seal any unused openings in the venting system.
2.  Inspect the venting system for proper size and horizontal pitch, as 
required in the National Fuel Gas Code, ANSI Z223.1or the CAN/
CGA B149 Installation Codes and these instructions. Determine 
that  there  is  no  blockage  or  restriction,  leakage,  corrosion  and 
other deficiencies which could cause an unsafe condition.
3.  So  far  as  is  practical,  close  all  building  doors  and  windows 
and all doors between the space in which the water heater(s) 
connected to the venting system are located and other spaces 
of  the  building.  Turn  on  all  appliances  not  connected  to  the 
venting system. Turn on all exhaust fans, such as range hoods 
and  bathroom  exhausts,  so  they  shall  operate  at  maximum 
speed. Close fireplace dampers.
4.  Follow  the  lighting  instruction.    Place  the  water  heater  being 
inspected  in  operation.    Adjust  thermostat  so  water  heater 
shall operate continuously.
5.  Inspect vent system for leakage after 5 minutes of main burner 
operation.
6.  After  it  has  been  determined  that  each  appliance  connected 
to the venting system properly vents when tested as outlined 
above,  return  doors,  windows,  exhaust  fans,  fireplace 
dampers and any other gas burning appliance to their previous 
conditions of use.  
						

							27
8. If  the  Ignition  Control  does  not  sense  the  pilot  flame  during  the 
ignition trial period, the Ignition Control shuts the Pilot Gas Valve 
and turns off the Spark Igniter. After 5 minute delay, a new trial for 
ignition  is  initiated. This  sequence  continues  until  the  unit  lights 
or “Call for Heat” is removed.
9.  If  the  pilot  flame  is  proved  during  the  ignition  trial  period,  the 
Ignition  Control  will  energize  the  main  gas  control  valve  to  start 
the  heating  cycle.  If  the  flame  signal  is  lost  during  the  heating 
cycle,  the  Ignition  Control  closes  the  gas  control  valve  and  re-
starts the ignition process at step 5.
10.  Once the unit is satisfied, the Thermostat will turn off the 24vac power 
to  the  blower  relay  and  the  Ignition  Control,  and  the  unit  will  be  in 
standby mode until another call for heat is initiated by the thermostat.
See the flow chart on page 28 for more detailed information.
SEQUENCE OF OPERATION
The  following  information  will  describe  the  Sequence  of  Operation 
for this water heater.
1.  Switch power on to unit.
2.  Thermostat calls for heat.
3.  Blower power relay is energized to start the blower.
4.  The blower pressure switch is closed, 24VAC power is applied to 
the Ignition Control Module.
5.  The  Ignition  Control  performs  diagnostic  self  check  on  system 
components.
6.  After  30  seconds  delay,  the  Ignition  Control  begins  the  trial  for 
ignition by turning on the Spark Igniter and the Pilot Gas Valve.
7.  The Ignition Control monitors the Flame Sensor during the ignition 
trial period.
LIGHTING & OPERATING LABEL
FIGURE 23.  
						

							28
SEQUENCE OF OPERATION FLOW CHART
Description of this flow chart can be found in the “SEQUENCE OF OPERATION” section found on page 27.
Thermostat calls f\uor heat
Switch power on to\u unit
\flower engages Prove\ur Switc h
\bgnition Control mo\unitors  
flame signal
Loss of flame sign\ual ?
YE
S
YES
NO NO
\flower power 
relay is energ ized to 
st art blower
\bgnion Contr ol provides power to Spa\urk  
\bgnite r and Pilot Gas V alve and monitor s 
Flame Sensor to de\ut ermine if \furner is\u lit
24V
AC power to the \bgn\uion  
Cont rol and self check
Tr ial  for ignio n
Spark O and Open \umain Gas V alve
5 minutes re try 
dela y
Close pilot 
gas 
va lve and Spark o
Flame Pro
ved?
Close Main valve 
and Pilot  valve
30 Seconds P repur ge
Thermos tat is sase d
\flower – o; \flower\u Pr over – opens
\bgnion Contr ol – o; Gas Valve – closes
FIGURE 24.  
						

							29
VENTING SYSTEM
Examine  the  venting  system  every  six  months  for  obstructions 
and/or  deterioration  of  the  vent  piping.  Check  all  vent  system 
connections for leakage and repair or reseal as necessary.
Remove  all  soot  or  other  obstructions  from  chimney  which  will 
retard free draft.
INTAKE AIR SCREEN
The intake air screen is attached to the inlet end of the combustion 
blower. Inspect the intake air screen every six months. The intake air 
screen should be cleaned of any buildup of debris or foreign material.
TEMPERATURE-PRESSURE RELIEF VALVE TEST
 Burn hazard.
  Hot water discharge .
  Keep clear of Temperature-  
Pressure Relief Valve 
discharge outlet .
It  is  recommended  that  the  Temperature-Pressure  Relief  Valve 
should  be  checked  to  ensure  that  it  is  in  operating  condition 
every 6 months.
When checking the Temperature-Pressure Relief Valve operation, 
make sure that (1) no one is in front of or around the outlet of the 
Temperature-Pressure  Relief  Valve  discharge  line,  and  (2)  that 
the water discharge will not cause any property damage, as the 
water may be extremely hot. Use care when operating valve as 
the valve may be hot.
To  check  the  relief  valve,  lift  the  lever  at  the  end  of  the  valve 
several times, see Figure 25. The valve should seat properly and 
operate freely.
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 and drain the water heater, see 
Draining and Flushing on page 30. Replace the Temperature-
Pressure  Relief  Valve  with  a  properly  rated/sized  new  one, 
see Temperature-Pressure Relief Valve on pages 13-14 for 
instructions on replacement.
FIGURE 25.
If  the  Temperature-Pressure  Relief  Valve  on  the  water  heater 
weeps  or  discharges  periodically,  this  may  be  due  to  thermal 
expansion.
NOTE: Excessive water pressure is the most common cause of 
Temperature-Pressure  Relief  Valve  leakage.  Excessive  water 
system  pressure  is  most  often  caused  by  "thermal  expansion" 
in  a  "closed  system."  See  Closed  Water  Systems  and  Thermal 
Expansion  on  page  13. The Temperature-Pressure  Relief  Valve 
is not intended for the constant relief of thermal expansion.
Temperature-Pressure Relief Valve leakage due to pressure build 
up  in  a  closed  system  that  does  not  have  a  thermal  expansion 
tank installed is not covered under the limited warranty. Thermal 
expansion tanks must be installed on all closed water systems.
DO NOT PLUG THE TEMPERATURE-PRESSURE RELIEF 
VALVE  OPENING.  THIS  CAN  CAUSE  PROPERTY  DAMAGE, 
SERIOUS INJURY OR DEATH.
Explosion Hazar d
Temperature-Pressure Relief  Valve
must comply with  ANSI Z21.22-
CSA  4.4 and  ASME code.
Properly sized temperature-
pressure relief valve must be
installed in opening provided.
Can result in overheating and
excessive tank pressure.
Can cause serious injury or death.
ANODE ROD INSPECTION
The  anode  rod  is  used  to  protect  the  tank  from  corrosion.  Most 
hot water tanks are equipped with an anode rod. The submerged 
rod sacrifices itself to protect the tank. Instead of corroding tank, 
water ions attack and eat away the anode rod. This does not affect 
water’s taste or color. The  rod  must  be  maintained  to  keep  tank 
in operating condition.
Anode deterioration depends on water conductivity, not necessarily 
water  condition.  A  corroded  or  pitted  anode  rod  indicates  high 
water conductivity and should be checked and/or replaced more 
often than  an anode rod that appears to be intact. Replacement 
of a depleted anode rod can extend the life of your water heater. 
Inspection should be conducted by a qualified technician, and at 
a minimum should be checked annually after the warranty period.
Artificially  softened  water  is  exceedingly  corrosive  because  the 
process substitutes sodium ions for magnesium and calcium ions.
The  use  of  a  water  softener  may  decrease  the  life  of  the  water 
heater tank.
The  anode  rod  should  be  inspected  after  a  maximum  of  three 
years and annually thereafter until the condition of the anode rod 
dictates its replacement. Anode rod replacement is not covered 
by warranty.
NOTE:  Artificially  softened  water  requires  the  anode  rod  to  be 
inspected annually.
MAINTENANCE  
						

							30
DRAINING AND FLUSHING
Burn harzard.
Hot water discharge.Keep  hands   clear  of  drain
valve  discharge.
It is recommended that the water heater storage tank be drained 
and  flushed  every  6  months  to  reduce  sediment  buildup.  The 
water heater should be drained if being shut down during freezing 
temperatures.
To Drain the Water Heater Storage Tank:
1.  Turn off the electrical supply to the water heater.
2.  Turn off the gas supply at the Main Gas Shutoff Valve if 
the  water  heater  is  going  to  be  shut  down  for  an  extended 
period.
3.  Ensure the cold water inlet valve is open.
4.  Open  a  nearby  hot  water  faucet  and  let  the  water  run  until 
the water is no longer hot.
5.  Close the cold water inlet valve to the water heater.
6.  Connect a hose to the water heater drain valve and terminate 
it to an adequate drain.
7.  Open the water heater drain valve and allow all the water to 
drain from the storage tank.
8.  Close  the  water  heater  drain  valve  when  all  water  in  the 
storage tank has drained.
9.  Close the hot water faucet opened in Step 4.
10.  If the water heater is going to be shut down for an extended 
period, the drain valve should be left open.
To Flush the Water Heater Storage Tank:
1.  Turn off the electrical supply to the water heater.
2.  Ensure the cold water inlet valve is open.
3.  Open  a  nearby  hot  water  faucet  and  let  the  water  run  until 
the water is no longer hot. Then close the hot water faucet.
4.  Connect  a  hose  to  the  drain  valve  and  terminate  it  to  an 
adequate drain.
5.  Ensure  the  drain  hose  is  secured  before  and  during  the 
entire flushing procedure. Flushing is performed with system 
water pressure applied to the water heater.
6.  Open the water heater drain valve to flush the storage tank.
7.  Flush the water heater storage tank to remove sediment and 
allow the water to flow until it runs clean.
8.  Close the water heater drain valve when flushing is completed.
9.  Remove the drain hose.
10.  Fill the water heater - see Filling The Water Heater in this manual.
11.  Turn on the electrical supply to place the water heater back 
in operation.
12.  Turn on the gas supply to the water heater at the Main Gas 
Shutoff Valve.
13.  Allow the water heater to complete several heating cycles to 
ensure it is operating properly.
PERIODIC REMOVAL OF LIME DEPOSITS FROM 
TANK TYPE COMMERCIAL WATER HEATERS
The  amount  of  calcium  carbonate  (lime)  released  from  water  is 
in  direct  proportion  to  water  temperature  and  usage,  see  chart.  
The higher the water temperature or water usage, the more lime 
deposits  are  dropped  out  of  the  water.  This  is  the  lime  scale 
which forms in pipes, heaters and on cooking utensils.
Lime accumulation may affect the life of equipment, the efficiency 
of the heater, and fuel consumption characteristics. The usage of 
water  softening  equipment  greatly  reduces  the  hardness  of  the 
water.  However,  this  equipment  does  not  always  remove  all  of 
the  hardness  (lime).  For  this  reason  it  is  recommended  that  a 
regular schedule for deliming be maintained.
The  time  between  cleaning  will  vary  from  weeks  to  years 
depending upon water conditions and usage.
The  depth  of  lime  buildup  should  be  measured  periodically. 
Heaters  equipped  with  cleanouts  will  have  about  2"  of  lime 
buildup  when  the  level  of  lime  has  reached  the  bottom  of  the 
cleanout opening. A schedule for deliming should then be set up 
based on the amount of time it would take for a 1" buildup of lime. 
It  is  recommended  that  the  water  heater  initially  be  inspected 
after 6 months.
Example 1:
Initial inspection after 6 months shows 1/2" of lime accumulation. 
Therefore, the heater should be delimed once a year.
Example 2:
Initial  inspection  after  6  months  shows  2"  of  lime  accumulation. 
Therefore, the heater should be delimed every 3 months.
FIGURE 26.
DELIMING SOLVENTS
UN•LIME  is recommended  for deliming.  UN•LIME  is a patented 
food grade acid which is safe to handle and does not create the 
harmful fumes which are associated with other products.
UN•LIME may be obtained from your dealer, distributor or water 
heater manufacturer. Order Part Number 9005416105, 1 gallon, 
packed 4 gallons per case or Part Number 9005417105, 5 gallon  
container.