GMES8 GCES8 Installation Instructions
24
8. Replace the door on the front of the furnace.
9. Open the manual gas valve external to the furnace.
10. Turn on the electrical power supply to the furnace.
11. Set the room thermostat to the desired temperature.
NOTE: There is an approximate 30 second delay between ther-
mostat energizing and burner firing.
FURNACE SHUTDOWN
1. Set the thermostat to lowest setting.
2. Turn off the electrical power supply to the furnace.
3. Remove the burner compartment door.
4. White-Rodgers valve: Push switch to the OFF position.
Honeywell valve: Slide the switch to the OFF position.
5. Close manual gas shutoff valve external to the furnace.
6. Replace the door on the unit.
GAS SUPPLY PRESSURE M EASUREM ENT
CAUTION
T
O
PREVENT
UNRELIABLE
OPERATION
OR
EQUIPM ENT
DAM AGE
,
THE
INLET
GAS
SUPPLY
PRESSURE
M UST
BE
AS
SPECIFIED
ON
THE
UNIT
RATING
PLATE
W ITH
ALL
OTHER
HOUSEHOLD
GAS
FIRED
APPLIANCES
OPERATING
.
HIGH VOLTAGE !
D
ISCONNECT
ALL
POW ER
BEFORE
SERVICING
OR
INSTALLING
THIS
UNIT
. M
ULTIPLE
POW ER
SOURCES
M AY
BE
PRESENT
. F
AILURE
TO
DO
SO
M AY
CAUSE
PROPERTY
DAM AGE
,
PERSONAL
INJURY
OR
DEATH
.
WARNING
MODELS USING SINGLE STAGE GAS VALVES
The line pressure supplied to the gas valve must be within the
range specified below. The supply pressure can be measured at
the gas valve inlet pressure tap or at a hose fitting installed in the
gas piping drip leg. The supply pressure must be measured with
the unit OFF. To measure inlet pressure, use the following proce-
dure.
White-Rodgers Model 36J22
Gas Valve On/Off
Selector Switch
Inlet
Pressure
Ta p
Pressure Regulator
(under cap screw)
Outlet
Pressure
Tap
Honeywell Model VR8215 (Single-Stage)
1. Turn OFF gas to furnace at the manual gas shutoff valve
external to the furnace.
2. Turn OFF all electrical power to the system.
3. Inlet pressure tap connections:
a. Honeywell Valve:
Remove the inlet pressure Tap plug. Install an 1/8” NPT
hose barb fitting into the outlet pressure tap.
b. White-Rodgers valve:
Back inlet pressure test screw (inlet pressure Tap out one
turn (counterclockwise, not more than one turn).
4. Attach a hose and manometer to the outlet pressure barb
fitting (Honeywell valve) or inlet pressure Tap White-
Rodgers valve).
5. Turn ON the gas supply.
6. Turn On power and close thermostat “R” and “ W” contacts
to provide a call for heat.
7. Using a leak detection solution or soap suds, check for
leaks at outlet pressure Tap plug (Honeywell valve) or screw
(White-Rodgers valve). Bubbles forming indicate a leak.
SHUT OFF GAS AND REPAIR ALL LEAKS IM MEDIATELY!
8. M easure the gas supply pressure with burners firing.
Adjust supply pressure using the Inlet Gas Supply Pressure
table shown below. If supply pressure reading differs from
the table, make necessary adjustments to pressure
regulator, gas piping size, etc., and/ or consult with local
gas utility.
Natural Gas Minimum: 4.5" w.c. Maximum: 10.0" w.c.
Propane Gas Minimum: 11.0" w.c. Maximum: 13.0" w.c.
INLET GAS SUPPLY PRESSURE
9. Turn OFF all electrical power and gas supply to the system.
10. Remove the manometer hose from the hose barb fitting
or inlet pressure Tap.
11. Replace inlet pressure tap:
a. Honeywell valve:
Remove the 1/8” NPT hose barb fitting from the inlet
pressure tap. Replace the inlet pressure Tap plug and
seal with a high quality thread sealer.
b. White-Rodgers valve:
Turn inlet pressure test screw in to seal pressure port
(clockwise, 7 in-lb minimum).
12. Retest for leaks. If bubbles form, shut down gas and repair
leaks immediately.