System Hub
HVAC Heating Systems
Gas furnaces, heat pumps in heating mode, and electric heat. Heating failure diagnostics and repair guides.
Common Heating Systems problems
Furnace Not Heating
The furnace fan is blowing, but the air is not warm or it won't stay lit.
Diagnostic pillar →Furnace Blowing Cold Air
The heater is active, but the air coming through the vents is room-temperature or cold.
Diagnostic pillar →Furnace Clicking but No Ignition
You hear the furnace trying to start, but no heat is produced.
Diagnostic pillar →