Thermon HELLFIRE 400, Installation, Operation & Maintenance Instructions Manual

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Problem Conditions* Possible Cause Remedy**
Heater fails to start.
Alarm indicated.
(cont’d)
ࢦ
Fan starts, runs
briefly then stops.
ࢦ
Controller LEDs
– POWER on.
–
ALARM red.
–
AIR SW
alternating.
Heater NOT connected to
duct system.
Complete heater installation.
Air intake severely blocked.
Clear intake screen of blockage,
i.e. ice, snow, paper.
Air switch fails to close when
fan operating.
Calibrate air switch.
See manual for instructions.
ࢦ
Fan starts.
ࢦ
Controller LEDs
–
POWER on.
–
MOTOR on.
– HEAT on.
Followed by:
– HEAT off.
–
ALARM red.
–
FSR ALARM
alternating.
ࢦ
Fan runs for post
purge duration then
stops.
– MOTOR off.
Inadequate gas pressure.
ࢦ
Verify supply pressure is within
nameplate rating.
ࢦ
Verify manual shutoff valve on top of
combination valve is open. Arrow in
line with body.
Air in line. Purge air from gas supply line.
No spark.
ࢦ
Inspect igniter and ignition wire.
ࢦ
Replace any damaged items, fouled
igniter, corroded wire or cracked boot.
Inadequate flame signal.
Inspect flame rod and wiring.
Replace any damaged items, fouled rod,
corroded wire or cracked boot.
ࢦ
Controller LEDs
–
POWER on.
–
ALARM red.
–
FSR CHECK
alternating.
DSI missing. Install DSI control module.
DSI failed.
DSI LED lit.
Unable to energize
combination gas valve.
Replace DSI control module.
Open circuit between
DSI ‘VALVE’ terminals and
combination gas valve.
Trace wiring. Repair damaged wires.
Tighten any loose connections.
Heater starts, runs for
10 minutes with no
heat, stops and then
alarm indicated.
ࢦ
Controller LEDs
–
POWER on.
–
ALARM red.
–
CYCLING
alternating.
Cycling thermostat failed
open.
Replace thermostat.
NOTE:
If thermostat closes the alarm is
cleared and the heater resumes
normal operation.
Cycling thermostat
disconnected.
ࢦ
Connect thermostat.
ࢦ
Inspect for damaged wiring between
control panel and thermostat box.