Page 16
High Efficiency - High Intensity
KMI_02142017al
TROUBLESHOOTING
SYMPTOM
POSSIBLE CAUSE
CORRECTIVE ACTION
Heaters will not turn off
Defective thermostat
Repair or replace
Stuck gas valve
Gas Odor
Loose pipe connection
Verify all connections
are sealed by using an
appropriate leak test
Burning of gas/air mixture
inside venturi (flashback)
Cracks between or across ceramic grids Replace burner head
assembly
Excessive drafts
Shield or relocate heater
Heaters Cycles on/off
Excessive drafts
Shield or relocate heater
Flame sense not grounded
Verify wiring and correct
Low gas pressure
Verify and correct
Low surface temperature on
ceramic surface
Dirty or plugged ceramics
See cleaning maintenance
Low inlet gas pressure
Verify and correct
Misaligned manifold/orifice
Replace manifold
Insufficient gas supply
Verify capacity of fuel supply
lines
No spark, no ignition
No power to control module
Verify and correct/replace
Control module defective
No power to spark electrode
No equipment ground
Heater sparks but will not light
No gas supply
Check shut off valve and
combination gas valve
Defective gas valve solenoid
Verify and correct/replace
Defective electronic control
Heater lights but 'locks out'
after about 10 seconds
Poor ground
Verify and correct/replace
Reversed polarity on electric supply
Sense electrode not sensing flame
Check continuity of sense
electrode
Defective electronic control
Verify and/or replace
