Instructions / Assembly
2. TEMPERATURE SETTINGS — The thermostat is adjusted 
to its lowest temperature position when shipped from the factory. 
To meet commercial water use needs, it is adjustable up to 180°F 
(82°C). However, water temperatures over 125°F (52°C) can cause 
severe burns instantly or death from scalds. This is the preferred 
starting point for setting the control for supplying general purpose 
hot water.
  Safety and energy conservation are factors to be considered when 
setting the water temperature on the thermostat. The most energy 
efficient operation will result when the temperature setting is the 
lowest that satisfies the needs consistent with the application.
Hotter water increases the Potential for Hot Water SCALDS.
When this  water heater  is supplying  general purpose hot water 
requirements for individuals, a thermostatically controlled mixing 
valve for reducing point of use water temperature is recommend-
ed. Contact a licensed plumber or the local plumbing authority for 
further information.
  Outlet water temperature will vary during normal operating cycles. 
Reliable temperature readings should be taken shortly after main 
burner cycles off during a period of little or no use.
3. GAS MANIFOLD PRESSURE — With the gas valve supplied 
with this water heater, main burner ignition occurs at a low or step 
manifold pressure, which will  then  automatically  build  up  to its 
normal operating level . On the Power Assist Burner and Xtreme 
units, ignition and manifold pressure occur immediately. The rated 
operating manifold pressure is  listed on the water heater rating 
plate. For  purposes of  input adjustment, the minimum inlet  gas 
pressure(with main burner on) is also shown on the rating plate. 
A 1/8” NPT tapping is provided on the outlet side of the gas valve 
for connecting a manometer to check this pressure. If necessary, 
adjust the pressure to the proper value by turning regulator adjust-
ment screw clockwise to increase pressure or counterclockwise to 
decrease pressure.
4.  CHECKINPUT —  Consult the local Gas Company to determine the 
heating value of the gas supplied. Check input by clocking gas meter with 
all other gas appliances turned off. Use the following formula:
DO NOT exceed Input shown on the water heater's rating plate!
  To insure accuracy for rating, clock enough cubic feet of gas so 
that the clocked time is at least 60 seconds. 
10
Operation
A.  Do turn off manual gas shut-off valve if water heater has been  sub-
jected  to over heating, fire, flood, physical damage or if gas supply 
fails to shut off.
B.  Do Not  turn on water heater unless it is filled with water.
C.  Do Not  turn on water heater if cold water supply shut-off valve is 
closed.
D.  Do  Not    store  or  use  gasoline  or  other  flammable  vapors  and 
liquids, such  as adhesives or paint thinner,  in vicinity of this  or any 
other appliance. If such flammables must be used, open doors and 
windows  for  ventilation,  and  all  gas  burning  appliances  in  vicinity 
should be shut off,  including  their pilot  lights, to avoid vapors  ignit-
ing.
  NOTE: Flammable  vapors may be  drawn  by  air cur-
rents from surrounding areas to the water heater.
E.  Do  not    allow combustible  materials such  as  newspaper,  rags  or 
mops to accumulate near water heater.
F.  If  there  is  any  difficulty  in  understanding  or  following  the  OPERA-
TION  or  MAINTENANCE  instructions,  it  is  recommended  that  a 
qualified person or serviceman perform the work.
Hydrogen gas can be produced in a hot water system served by 
this water heater that has not been used for a long period of time 
(generally two weeks or more). HYDROGEN GAS IS EXTREMELY 
FLAMMABLE!! To dissipate such gas and to reduce risk of injury, 
it is recommended that the hot water faucet be opened for sev-
eral minutes at the kitchen sink before using any electrical appli-
ance 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. Do not  smoke or 
use an open flame near the faucet at the time it is open.
SAFETY PRECAUTIONS
CAUTION
!
INPUT (btu/h) = 
(3,600) x (Heating Value) x (Number of Cubic Feet Timed)
Seconds Clocked
DANGER
!
Figure 6. — Thermostat adjustment
120
140
°
F
1
8
0
1
6
0
1
4
0
1
3
0
1
2
0
1
1
0
1
0
0
THERMOST AT
°
C
8
0
7
0
6
0
5
0
4
0
To adjust the water temperature, insert a small straight 
screwdriver into slotted screw in hole in front of 
thermostat and turn wheel to desired setting.  Ther-
mostat is adjustable up to 180º F.
CAUTION!!  - Hotter water increases the risk of SCALDING!
White-Rodgers
Honeywell
WARNING
!
WARNING
!










