Gas Furnace Symptoms
Heating Mode
Standard Furnace Diagnostic Codes
Indoor Blower and Inducer Motor Running/Unit Will Not Fire
Furnace Short Cycling
Inducer Motor Runs/ Unit Will Not Fire
Burners Will Not Light
Nothing Runs/Unit Will Not Fire
Some Burners Light/Others Do Not
Sooting
Combustion Air Inlet Freezing (90% Furnaces)
Roll Out Limit Tripping
Delayed or Rough Ignition
Main Limit Tripping
Flame Distortion
Heat Assisted Limit Tripping
Pilot Outage
Water Build Up In Secondary Heat Exchanger (90% Furnaces)
Noisy Pilot
Water Formation In Primary Heat Exchanger (GTA/GTJ)
Lazy Pilot
Burner Short Cycling/No Amber Light
Main Burner Noisy
Main Blower Noisy
Moisture or Rust Inside Furnace
Intermittent or Erratic Operation
Insufficient Heat
Indoor Blower Runs Constantly
No Furnace Operation, Green Lights Flashing(Twinned Furnaces)
HSI Not Heating
Inducer Noisy
Electrodes Not Sparking (DSI)
Rust in Vent Pipe and/or Burner Area
Pressure Switch Not Closing
Furnace Overheating Building
Does Not Sense Flame
Leaking Water (90% Furnaces)
Burner Short Cycling/Amber Light Glows