13
IX405 Operation & Service Manual
P/N 974-1184 Rev: 1.50
Other problems during operation
Symptom
Possible Problems
Small or poor quality flame. Manifold
pressure drops below rated value in
function. Heater ignites but may shut off
with three flashes on Ignition Control error
light.
Propane tank too small to vaporize fast
enough, tank freezes.
Gas Hose too small, too long, or blocked.
Inlet pressure too low.
Gas Selector Valve set to wrong fuel.
Burner air inlet obstructed.
Heater shuts off unexpectedly with three
flashes on Ignition Control error light.
Blocked exhaust.
Flame rod failure.
Out of fuel.
Solenoid Valve failure.
Output limit switch failure.
Ignition Control failure.
Burner cycles on and off frequently.
Fan Limit Switch settings incorrect.
Ducts too long, too small, or obstructed.
Excessive yellow flame. Rumbling noise
during flame ignition.
Changeover valve set to wrong fuel.
Heater connected to liquid propane supply.
Manifold pressure set too high.
Heater does not stop when Stop Button is
pressed.
Stop Switch failure.
Start Switch failure.
Logic Relay failure.
Excessive noise or vibration.
Damaged or unbalanced Burner Impeller.
Damaged or unbalanced Blower Impeller.
Blower Motor runs constantly.
Blower Relay failure.
Fan Limit Switch set in manual position.
Fan Limit Switch settings incorrect (fan off-
pointer set to low).
Heater does not turn off when thermostat
turned to minimum. No lights on Ignition
Control.
Thermostat failure.
Heater does not turn off when thermostat
turned to minimum. Two flashes on
Ignition Control error light.
Solenoid valve stuck open.
Solenoid valve leaking.