Every time your thermostat calls for heat, the furnace runs a fixed checklist. The inducer motor starts and proves draft by closing a pressure switch, the hot surface igniter heats up, the gas valve opens, the burners light, and the flame sensor confirms there is fire. Only after all of that does the blower start pushing warm air into the house. Finding the step that fails is most of the job. Around Davis, CA, the usual failure points are a flame sensor fouled with oxide, an igniter cracked by years of heating and cooling, a pressure switch that stays open because of a weak inducer or a clogged condensate trap on a high-efficiency unit, and control boards with burned relays. Any one of them halts the startup, and from the hallway they all look alike.
When the AC quits in summer, see AC Repair.
When to Call for Furnace Repair in Davis
Catching these issues early helps you avoid costly problems. Keep an eye out for the following clues:
- Air moving through the vents that never gets warm
- Water, rust stains, or black soot around the flue or cabinet
- Frequent on-off cycling that never reaches the thermostat setting
- Repeated shutdowns just seconds after the burners light
- Booming or banging at light-off from delayed ignition
- A pilot or burner flame that is lazy yellow instead of crisp blue
- The igniter glows and clicks, yet no flame ever appears
- Grinding or high-pitched squeals from the blower
Act Before It Gets Worse
What seems like a minor issue today can take out a compressor or heat exchanger tomorrow. At the first hint of a problem, call (530) 201-3647 for a fast inspection.
