- 16 -
Status Code 2
PRESSURE SWITCH DID NOT OPEN - This status code indicates the low, medium, or high pressure switch LPS, MPS, or
HPS is made when a call for heat is initiated. The modulating furnace control will flash status code 2 until the switch opens,
then cycle begins.
STEP
ACTION
YES
NO
GO TO
1.
Turn power off, remove blower door, and disconnect communication connector PL7 (if used)
or the R thermostat lead (if used) from the furnace control board.
2
2.
Turn power on and depress door switch. Use a piece of tape to hold switch closed.
3
3.
Jumper R, W/W1, and W2 thermostat terminals.
4
4.
Does status code 2 flash?
8
5
5.
Does a different status code flash?
6
7
6.
Go to page number indicated in the Index for the section covering the status code.
INDEX
7.
Go to page number indicated in Index for CLEANUP AND START-UP INSTRUCTIONS.
INDEX
8.
Is the inducer motor ON?
18
9
9.
Is 24-vac across ORANGE wire on the low pressure switch LPS and C
OM
-24V on
modulating furnace control?
15
10
10.
Is 24-vac across connector terminal PL1-4 and C
OM
-24V on modulating furnace control?
11
12
11.
The main harness is miswired.
7
12.
Is 24-vac across VIOLET wire on the medium pressure switch MPS and C
OM
-24V on
modulating furnace control?
15
13
13.
Is 24-vac across connector terminal PL1-3 and C
OM
-24V on modulating furnace control?
11
16
14.
Replace modulating furnace control.
7
15.
Replace the pressure switch assembly.
7
16.
Is 24-vac across BROWN wire on the high pressure switch HPS and C
OM
-24V on
modulating furnace control?
15
17
17.
Is 24-vac across connector terminal PL8-4 and C
OM
-24V on modulating furnace control?
11
14
18.
Check the inducer PWM line. To do this disconnect 3-pin connector PL16 from the inducer
motor or the inducer motor adapter harness (when used), and connect a DC voltmeter across
terminals PL16-1 BROWN (+) and PL16-2 YELLOW (-).
Note:
The terminals can be permanently damaged if the voltmeter probe is jammed into the
terminal end of the connector. Use caution when checking.
Run COMPONENT TEST by turning setup switch SW1-6 ON. Does voltage across PL16-1
and PL16-2 change between states as shown below?
- State 1 – OFF (1.0 – 4.0 vdc)
- State 2 – MED (6.0 – 10.0 vdc)
19
14
19.
Replace the inducer motor control (if you have 2 piece design) or the inducer motor
assembly.
7
440 08 4001 00
