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440 01 2020 01
HONEYWELL SV9541Q “SMART VALVE” Trouble shooting
The 6 + X designation indicates a combination of flash codes: 6 flashes shows the control is in soft lockout, followed by X flashes to indicate
the reason the control went into soft lockout. Last status code indicates repair to address first
LED
STATUS
INDICATES
CHECK/REPAIR
Off
No power to system control.
Line voltage input at L1 and Neutral connectors on ST9162A Fan Timer.
Low voltage (24V) power at 24 VAC and COM terminals on ST9162A
System wiring harness is in good condition and securely connected.
Heartbeat
Bright – Dim
Normal indication whenever the system is powered, unless some
abnormal event has occurred.
Not Applicable
--
Normal Operation (stand by or call for heat)
2 Flashes
Low pressure switch closed when it should be open
(i.e. when call for heat begins).
(Combustion blower is not energized until pressure switches
opens)
Pressure switch stuck closed (system will wait for pressure switch to
open).
Pressure switch miswired or jumpered.
3 Flashes
Low pressure switch, open when it should be closed (i.e. longer
than 30 seconds after combustion blower/inducer is energized).
System goes into 5--minute delay period, with combustion blower/
inducer off. At end of the 5--minute delay, another cycle will begin.
Ignition system control switch must be in the ON position.
Pressure switch operation, tubing, and wiring.
Restrictions in furnace air intake or vent piping.
4 Flashes
Main Limit or Roll Out Switch is open.
Combustion blower is energized, Circulating blower is energized
heat speed.
Main limit switch.
Manual reset burner rollout switch.
Limit and rollout switch wiring is in good condition and securely
connected.
5 Flashes
Flame signal sensed out of proper sequence.
Combustion blower is energized, Circulating blower is energized
heat speed after the “ON” delay.
Flame at pilot burner.
6 Flashes
+
1 Flash
Soft Lockout.
Failed to light pilot during 90 sec. trial for ignition
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,
Gas supply off or pressure too low or high for appliance to operate.
Damaged or broken HIS element
Line voltage HOT lead wire not connected to L1 terminal on ST9162A.
Furnace not properly earth grounded.
Flame sense rod contaminated or in incorrect position.
Pilot burner located in incorrect position.
Pilot burner lead wires are in good condition and popery connected.
Pressure switches operation, tubing, and wiring.
6 Flashes
+
2 Flashes
Soft Lockout.
Last failure was Flame Sense lost during run.
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,
Gas supply off or pressure too low or high for appliance to operate.
Line voltage HOT lead wire not connected to L1 terminal on ST9162A.
Furnace not properly earth grounded.
Flame sense rod contaminated or in incorrect position.
Pilot burner located in incorrect position.
Pilot burner lead wires are in good condition and properly connected.
Cycling, pressure switch
Condensate drain blocked
Pressure switches operation, tubing, and wiring.
Summary of Contents for 9MPT050F12A
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