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30
STEP
ACTION
YES
NO
GO TO
14.
Is 24--vac across ORANGE wire on the low heat pressure switch LPS and C
OM--24
V on
variable speed furnace control?
15
19
15.
Is 24--vac across connector terminal PL1--4 and C
OM--24
V on variable speed furnace con-
trol?
18
16
16.
Turn power off and disconnect jumper wire across R and W/W1 thermostat terminals.
17
17.
You have an open circuit between the low heat pressure switch LPS and the variable speed
furnace control. This includes all the ORANGE wire interconnecting the low heat pressure
switch LPS to the variable speed furnace control. It also includes the low gas pressure
switch LGPS (if used).
Check the continuity across the low gas pressure switch LGPS (if used). If there is no con-
tinuity check the propane line pressure. If the propane line pressure is correct replace the
low gas pressure switch LGPS.
Check the continuity of each ORANGE wire interconnecting the low heat pressure switch
LPS and the variable speed furnace control. Repair open wire or replace harness.
8
18.
Replace the variable speed furnace control.
8
19.
Replace the low heat pressure switch or the pressure switch assembly.
8
Status Code 45
CONTROL CIRCUITRY LOCKOUT -- This status code indicates the variable speed furnace control detected one of the
following:
1. Flame sense circuitry failure.
2. Software check error.
3. Gas valve relay stuck open.
Auto--reset after 1 hour. Replace variable speed furnace control if status code repeats.
CLEANUP AND START--UP INSTRUCTIONS
1.
Start furnace using procedure outlined on Lighting Instructions attached to furnace. Observe operation of furnace through at least 1 complete
heating cycle controlled from the room thermostat. Observe cycle for 20 minutes or until a status code is flashed. If status code flashes, refer to
the Index.
2.
Recycle as necessary and check thermostat heat anticipator setting, gas input rates, and temperature rises. These procedures are outlined in
Installation, Start--Up, and Operating Instructions.
3.
Check operation of safety devices: limit switch and flame rollout switch.
4.
Put all setup switches in their proper positions.
5.
Remove tape from the door switch.
6.
Replace thermostat leads (if necessary).
7.
Set thermostat in AUTO position, calling for heat.
8.
Set thermostat to desired temperature.
9.
Replace the blower access panel and furnace door. Clean up.