6
6.3
Fault messages
Fault message
Description of malfunction
Trouble shooting
IMF-X: Ignition failed
All burners have produced an ignition
module failure. No burners are available
to produce steam.
Unit unsafe to operate. Recover the prob-
lem before restarting unit.
1. Make sure gas supply is connected
and open.
. Check for correct gas supply pressure
as indicated on the rating plate.
. Check that igniter turns red hot during
ignition sequence.
4. If igniter is red hot but no flame is vis-
ible, check for 4 VAC at gas valve.
5. If flame is visible, check connection to
flame sensor. Ensure supply voltage
L1 is not wired to N.
AOF-X: AirProving open
The corresponding air proving switch did
not close during blower start-up after
attempts.
Unit unsafe to operate. Recover the prob-
lem before restarting unit.
1. Make sure air proving switch is properly
connected to driver board.
. Make sure pressure tubes are se-
cure.
. Make sure air flows into blower dur-
ing blower operation. If no suction is
detectable, the blower might need to
be replaced.
4. Perform diagnostic output test on
blower RPM to verify that air proving
switches remain closed during opera-
tion
5. If air proving switch does not close
during operation it might need to be
replaced.
ACF-X: Airproving closed
The corresponding air proving switch was
closed while the blowers were inactive.
The unit will remain in fault mode until
the problem is recovered or the unit is
reset.
1. Make sure air proving switch is properly
connected to driver board.
. Make sure pressure tubes are se-
cure.
. Perform output test in diagnostic menu
to ensure switches close and open with
blower operation.
4. Check/Replace air proving switch.
BNF-X: Blower fault
The corresponding blower is not operating
or the measured speed is below 500 RPM
while the blower is running.
Unit unsafe to operate. Recover the prob-
lem before restarting unit.
1. Check electrical connections. Make
sure both feedback and power are
connected.
. Make sure relay is operating. Check
voltage on both sides of relay.
. Check if a RPM reading is shown in
RPM info screen for the corresponding
fan.
4. Check if blower is operating. If op-
erating, feedback signal could be a
problem.
5. If blower is not operating, check power
supply
GVF-X: Gas valve fault
The corresponding gas valve was en-
ergized out of sequence or when not
expected to be energized.
Unit unsafe to operate. Recover the prob-
lem before restarting unit.
1. Ensure electronics are connected ac-
cording to the wiring diagram
. Check connections to ignition mod-
ules.
. Verify adequate supply voltage.