4. Turn high-heat stage adjusting screw (3/32-in. hex allen wrench) clockwise (in) 2 fulll turns. This will increase the manifold pressure
closer to the propane high-heat set point. Replace caps that conceal gas-valve regulator adjustment screws. Go to Procedure 3.
PROCEDURE 3—INSTALL LOW GAS PRESSURE SWITCH (LGPS)
NOTE:
The inlet gas pipe must be disconnected from valve so pressure switch can be installed.
NOTE:
Use propane-gas-resistant pipe dope on all connections to prevent gas leaks. DO NOT use Teflon tape.
1. Be sure main gas and electric supplies to furnace are off.
2. Remove 1/8-in. pipe plug from inlet pressure tap on gas valve. (See Fig. 6A, 6B or 6C, 6D and Fig. 7A and 7B.) DO NOT DISCARD 1/8
″
PLUG.
3. Apply pipe dope sparingly to one end of 1/8
″
brass male coupling (provided in kit) and install the doped end in 1/8-in. tapped opening in
gas valve inlet pressure-tap. Tighten fitting with a small open-end wrench. (See Fig. 7A and 7B.)
4. Apply pipe dope sparingly to opposite end of the 1/8
″
brass coupling (provided in kit). Install the female end of the female x female x male
tee on the brass coupling. Tighten coupling finger tight. Use a small open-end wrench for final tightening.
5. Apply pipe dope sparingly to male end of brass tee. Install propane low gas pressure switch (provided in kit) on male end of the female
x female x male tee. Tighten switch finger tight. Use a small open-end wrench on base of pressure switch for final tightening.
6. Connect a manometer to the open end of the tee installed in the gas valve. (See Fig. 7A and 7B.)
7. Apply pipe dope sparingly to end of inlet gas pipe and reconnect pipe to gas valve.
→
Fig. 6C—Two-Stage Gas Valve
A04048
REGULATOR COVER SCREW
PLASTIC ADJUST SCREW
LOW STAGE
GAS PRESSURE
REGULATOR ADJUSTMENT
(
PROPANE–WHITE, 9.5 TURNS
NATURAL–SILVER,9.5 TURNS)
MANIFOLD
PRESSURE TAP
INLET
PRESSURE TAP
ON/OFF SWITCH
REGULATOR SPRING
HIGH STAGE GAS
PRESSURE REGULATOR
ADJUSTMENT
(
PROPANE–WHITE, 13.5 TURNS
NATURAL–SILVER,12 TURNS
)
Fig. 6D—Two-Stage Gas Valve
A01069
ON
O
F
F
ON/OFF
SWITCH
INLET
PRESSURE
TAP
BURNER ENCLOSURE
REFERENCE PRESSURE TAP
(2-STAGE
AND VARIABLE-SPEED, CONDENSING
FURNACES ONLY)
MANIFOLD
PRESSURE
TAP
LOW-HEAT
ADJUSTMENT
ALLEN SCREW
(UNDER CAP)
HIGH-HEAT
ADJUSTMENT
ALLEN SCREW
(UNDER CAP)
PLUG BUTTON
(2-STAGE AND
VARIABLE–SPEED,
NON–CONDENSING
FURNACES ONLY)
—7—
