22
I-RIH (05-21) 131793-A
TROUBLESHOOTING
Refer to
for general troubleshooting symptoms, probable causes, and remedies .
Table 8. General Troubleshooting
Symptom
Probable Cause
Remedy
A . Gas odor 1 . Gas pipe joints loose
Leak test joints and tighten as necessary
B . New
installation
of heaters
not working
1 . Heaters not isolated during high pressure leak
testing of gas lines
Replace combination gas valve(s) on each heater
2 . All gas lines not completely bled of air
Disconnect flex hose at each heater until gas is present
Connect flex hose and leak test
3 . Gas supply regulator reversed
Remove gas supply regulator and install properly
4 . Electrical supply line voltage and neutral polarity
reversed
Correct electrical supply polarity
C . No gas
1 . Gas supply valves not open
Open all manual gas supply valves
2 . Gas supply regulator sticking
Replace gas supply regulator
D . Electrical
circuit
closed but
heater not
working
1 . Gas supply lacking caused control system lockout
Ensure that all gas supply valves are open
Purge air from gas supply line
Turn thermostat off, wait 5 minutes, and then reset thermostat
2 . Line fuse blown or tripped circuit breaker
Replace line fuse or reset breaker
3 . Electrical power short
Trace and correct short
4 . Wiring disconnected
Ensure that wiring connections are in accordance with wiring diagram
5 . No electrical earth ground
Provide electrical earth ground
6 . Electrical supply line voltage and neutral polarity
reversed
Correct electrical supply polarity
7 . Exhaust fan interlock (if used) is defective
Replace exhaust fan interlock
E . Direct
spark fails
to ignite
main
burner(s)
1 . Combination gas valve not in ON position
Turn combination gas valve to ON position
2 . Electrode wire loose
Reconnect wire
3 . Electrode wire broken or frayed
Replace electrode
4 . Electrode ceramic cracked
Replace electrode
5 . Electrode improperly located
Relocate to correct position
6 . Gas valve fails to open when power is applied
Replace combination gas valve
7 . Supply/manifold gas pressure too low
Adjust pressure in accordance with rating plate
8 . Ignition detection control defective
Replace ignition detection control
F . Unit
cycles on
and off
(erratic
operation)
1 . Drafty condition
Shield heater and/or thermostat from drafts
2 . Flame sensor wire loose or damaged
Replace wire harness to ignition detection control
3 . No electrical earth ground
Provide electrical earth ground
4 . Electrical supply line voltage and neutral polarity
reversed
Correct electrical supply polarity
5 . Heat on pilot flame sensor insufficient
Clean pilot and check pilot orifice and alignment
G . No pilot
1 . Gas line contains air
Purge air from gas line
2 . Pilot line, orifice, or passage blocked
Check and clean in accordance with
3 . Pilot solenoid valve inoperative
Replace combination gas valve
H . Pilot
goes out on
100% shut-
off when
hold-down
button is
released
1 . Heat on pilot flame sensor insufficient
Clean pilot and check pilot orifice and alignment
2 . Pilot flame sensor location improper
Correct position with respect to pilot
3 . Manifold gas pressure low
Adjust pressure in accordance with rating plate
4 . Poor contact at valve end of sensing element
Ensure clean and proper sensing element contact
5 . Pilot flame sensor defective
Replace pilot flame sensor
6 . Pilot interrupter in combination gas valve defective Replace combination gas valve
I . Pilot
burning
but no gas
to main
burner(s)
1 . Thermostat or manual switch open
Raise thermostat setting or close switch
2 . Manual valve closed on combination gas valve
Turn valve to ON position
3 . No power to solenoid in combination gas valve
Check power supply and furnish proper voltage
4 . Heat on pilot flame sensor insufficient
Clean pilot and check pilot orifice and alignment
5 . Pilot flame sensor defective
Replace pilot flame sensor
6 . Combination gas valve defective
Replace combination gas valve
J . Heater
will not turn
OFF
1 . Thermostat defective
Replace thermostat
K . Controls
overheated
1 . Heater mounted incorrectly
