54
SERVICING
NOTE:
At either location, a hose fitting must be installed
prior to making the hose connection.
NOTE:
Use apapter kit #0151K00000S to measure gas pres-
sure on White-Rodgers 36J22 gas valves.
GAS LINE
GAS SHUTOFF VALVE
GAS LINE
TO FURNACE
DRIP LEG CAP
WITH FITTING
MANOMETER HOSE
MANOMETER
OPEN TO
ATMOSPHERE
Measuring Inlet Gas Pressure
(Alternate Method)
3. Turn ON the gas and electrical power supply and oper-
ate the furnace and all other gas consuming appliances
on the same gas supply line.
4. Measure furnace gas supply pressure with burners fir-
ing. Supply pressure must be within the range specified
in the following table.
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
If supply pressure differs from above, make necessary ad-
justments to pressure regulator, gas piping size, etc., and/
or consult with local gas utility.
WARNING
HIGH
VOLTAGE
D
ISCONNECT
ALL
ELECTRICAL POWER AND SHUT OFF GAS
SUPPLY BEFORE SERVICING OR INSTALLING THIS UNIT.
M
ULTIPLE POWER SOURCES MAY BE PRESENT.
F
AILURE TO
DO SO MAY CAUSE PROPERTY DAMAGE, PERSONAL INJURY OR DEATH.
5. Disconnect manometer after turning off gas at manual
shutoff valve. Reinstall plug before turning on gas to fur-
nace.
6. Turn OFF any unnecessary gas appliances started in
step 3.
7. Turn on gas to furnace and check for leaks. If leaks are
found, repair and then reinstall burner compartment door.
8. Turn on electrical power and verify proper unit operation.
Gas Manifold Pressure Measurement and Ad-
justment
n
a
c
e
T
O PREVENT UNRELIABLE OPERATION OR EQUIPMENT DAMAGE, THE
GAS MANIFOLD PRESSURE MUST BE AS SPECIFIED ON THE UNIT
RATING PLATE.
O
NLY MINOR ADJUSTMENTS SHOULD BE MADE BY
ADJUSTING THE GAS VALVE PRESSURE REGULATOR.
CAUTION
NOTE:
Use apapter kit #0151K00000S to measure gas
pressure on White-Rodgers 36J22 gas valves.
Only small variations in gas pressure should be made by
adjusting the gas valve pressure regulator. The manifold
pressure must be measured with the burners operating. To
measure and adjust the manifold pressure, use the follow-
ing procedure.
WARNING
HIGH
VOLTAGE
D
ISCONNECT
ALL
ELECTRICAL POWER AND SHUT OFF GAS SUPPLY
BEFORE SERVICING OR INSTALLING.
1. After turning off gas to furnace at the manual gas shutoff
valve external to the furnace, remove burner compart-
ment door to gain access to the gas valve.
2. Connect a calibrated water manometer (or appropriate
gas pressure gauge) at the gas valve outlet pressure
tap. Refer to
Measuring Gas Pressure: Single Stage
Valves
figure for single stage valve outlet pressure tap
connections.
L
INE VOLTAGE NOW PRESENT
WARNING
3. Turn ON the gas and electrical power supply and oper-
ate the furnace.
4. Measure gas manifold pressure with burners firing. Ad-
just manifold pressure using the table below.
3.5" w.c.
10.0" w.c.
Manifold Gas Pressure
Natural Gas
Propane Gas
The final manifold pressure must not vary more than ± 0.3 “
w.c. from the above specified pressures. Any necessary
major changes in gas flow rate should be made by chang-
ing the size of the burner orifice.
5. White-Rodgers 36G22 Valves:
a. Back outlet pressure test screw (inlet/outlet pres-
sure boss) out one turn (counterclockwise, not more
than one turn).