Two- Stage Multi Position Furnace
Service Manual
41
440 08 2002 02
HONEYWELL SV9541Q “SMART VALVE” Trouble shooting continued
LED
STATUS
INDICATES
CHECK/REPAIR
6 Flashes
+
3 Flashes
Soft Lockout.
Last failure was pressure switch
Maximum recycle count exceeded
Combustion air blower is de--energized, Circulating
blower is de--energized after the “OFF” delay.
After 5--minute delay time, control system will reset
and initiate a new ignition sequence,
Ignition system control switch must be in the ON position.
Pressure switches operation, tubing, and wiring.
Restrictions in furnace air intake or vent piping.
High winds blowing against vent.
6 Flashes
+
4 Flashes
Soft Lockout.
Last failure was limit circuit opened during run.
Combustion air blower is de--energized, Circulating
blower
is
de--energized after the “OFF” delay.
After 5--minute delay time, control system will reset
and initiate a new ignition sequence,
Main limit switch.
Limit and rollout switch wiring is in good condition and se-
curely
connected.
Restriction in duct work.
Dirty filter
7 Flashes
Soft Lockout.
Blower failure (typical)
Limit trip took longer than 2 minutes to reset.
System will start a new ignition sequence after 1 hour,
if call for heat still present.
Dead blower.
Blocked duct work.
8 Flashes
High Pressure closed when should be open. (i.e.,
when call for heat begins).
(Combustion blower is not energized until pressure
switches open)
Pressure switches stuck closed (system will wait for pres-
sure switch to open).
Pressure switch miswired or jumpered.
9 Flashes
High Pressure open when should be closed. (i.e., lon-
ger than 30 seconds after combustion/inducer is ener-
gized).
System goes into a 5 minute delay period with com-
bustion blower/inducer “OFF”. At end of the 5 minute
delay another cycle begins.
Ignition system control switch must be in the “ON” position.
Pressure switch operation, tubing and wiring.
Restrictions in furnace air intake or vent piping.