GPGM3 Installation Manual
16
The line pressure supplied to the gas valve must be within the
supply pressure can be measured at the gas valve inlet pres-
The supply pressure must be measured with the unit OFF. To
measure inlet pressure, use the following procedure.
Regulator Cover
Screw
Mode
10.0
Inlet
Pressure
Boss
Low Fire
Regulator
Adjust
M
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r
Manometer
H
o
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e
High Fire Regulator
Adjust
Regulator
Vent
Outlet
Pressure Boss
Open to
Atmosphere
O
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/
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S
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c
h
H
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h
F
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C
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(
H
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C
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C
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(
M
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Common
Terminal(C)
White-Rodgers Model 36G54 Connected to Manometer
Mode
10.0
1.
valve external to the furnace.
2. Turn OFF all electrical power to the system.
3.
4. Attach a hose and manometer to the inlet pressure
5. Turn ON the gas supply.
6. Turn On power and close thermostat “R” and “W” con-
tacts, or “R” and “W1” + “W2” for two-stage models, to
provide a call for heat.
7. Using a leak detection solution or soap suds,
check for leaks at the inlet and outlet pressure taps
leak. SHUT OFF GAS AND REPAIR ALL LEAKS
IMMEDIATELY!
8.
Adjust supply pressure using the Inlet Gas Supply
Pressure table shown below. If supply pressure read-
-
ments to pressure regulator, gas piping size, etc., and/
or consult with local gas utility.
Propane Gas
Natural Gas
Inlet Gas Supply Pressure
9. Turn OFF all electrical power and gas supply to the
system.
10. Remove the manometer hose from the inlet pressure
boss.
Turn inlet pressure test screw in to seal pressure
12. Retest for leaks. If bubbles form, shut down gas and
repair leaks immediately.
13. Turn ON electrical power and gas supply to the system.
14. Turn valve switch ON.
Mode
10.0
CAUTION