Is 24 volts present,
measured across PS2?
(brown to yellow)?
See Note #1
Note #1
24 volts = Open Switch
0 volts = Closed Switch
DEFINITION
An error has occurred with the PS2, indica!ng that the pressure
switch is closed when it should be open.
In most cases, the pressure switch is not the problem.
NOTE: Verify pressure switch wiring and tube rou!ng
are correct.
3.3 Fault Code
Cycle power OFF, then ON to
the furnace
NO
Replace pressure
switch
Verify wiringYES