2. Remove 1/8-in. pipe plug from inlet pressure tap on gas valve. (See Fig. 22A, 22B, 22C, or 22D.) DO NOT DISCARD PLUG!
3. Apply pipe dope sparingly to the ends of the 1/8
″
brass male coupling (provided in kit) and install it in 1/8-in. tapped opening in gas valve
inlet pressure-tap. Tighten fitting with a small wrench.
4. Attach the female end of the female x female x male brass tee (provided in kit). Tighten fitting with a small wrench so the male portion
of the tee points out from the furnace.
5. Apply pipe dope sparingly to male end of bras tee. Install propane low gas pressure switch (provided in kit) on nipple. After switch has
been finger tightened, use small wrench on base of pressure switch for final tightening. When pressure switch is tight, switch terminals
should point as shown in Fig. 22A, 22B, 22C, or 22D relative to gas valve and clear control compartment access door.
6. Connect a manometer to the open end of the tee installed in the gas valve.
PROCEDURE 7—CHECK INLET GAS PRESSURE
NOTE:
This kit is to be used only when inlet gas pressure is between 11.0-in. wc and 13.6-in. wc.
1. Verify manometer is connected to inlet pressure tap on gas valve.
CAUTION: UNIT DAMAGE HAZARD
Failure to follow this caution may result in flame rollout, overheating the heat exchangers, etc. and reduce unit life.
DO NOT operate furnace more than 1 minute to check inlet gas pressure, as conversion is not complete at this time.
2. Turn on furnace power supply.
3. Turn gas supply manual shutoff valve to ON position.
4. Turn furnace gas valve switch to ON position.
5. For single stage models, jumper R to W.
6. For two-stage and variable speed models, perform the following steps to force furnace control board to high-heat operation.
For Two-Stage furnaces with HK42FZ017 board, perform the following on the control board:
–Turn LHT switch on furnace control to ON (See Fig. 8C.)
For Two-Stage furnaces with HK42FZ010 or HK42FZ015 boards, perform the following on the control board:
–Turn switch #2 on furnace control board to ON. (See Fig. 17A and 17B.)
For Variable Speed furnaces using HK42FZ012 control boards, perform the following on the control board:
–Turn Setup Switch SW1-2 on furnace control ON. (See Fig. 23.)
For Variable Speed furnaces using HK42FZ022 control boards, perform the following on the control board:
–Turn Setup Switch SW1-2 on furnace control ON. (See Fig. 8D.)
7. Jumper R-W/W1 and R-W2 thermostat connections on control.
8. When main burners ignite, confirm inlet gas pressure is between 11.0-in. w.c. and 13.6-in. w.c.
9. Remove jumper across R to W or R-W/W1 and R-W2 thermostat connections to terminate call for heat.
10. Turn furnace gas valve switch to OFF position.
Fig. 22D—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)
—24—
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