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 begin sending warm air into the house. Finding the step that fails is most of the job. Around Berkeley, CA, the usual failure points are an oxide-coated flame sensor, 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. Each one halts the startup, and from the hallway they all look alike.
For air conditioning breakdowns, see AC Repair.
When to Call for Furnace Repair in Berkeley
Spotting the early warning signs lets you act before the problem gets expensive. Watch for these telltale signs:
- Frequent on-off cycling that never reaches the thermostat setting
- The blower runs constantly but the air never warms
- The furnace clicks and glows but the burners never light
- Loud booms at startup caused by delayed ignition
- Squealing or grinding from the blower compartment
- Repeated shutdowns just seconds after the burners light
- A flame that burns soft and yellow rather than steady blue
- Rust streaks, soot, or water around the cabinet or flue
Act Before It Gets Worse
Most HVAC failures start small, a weak capacitor, a squealing blower, a system that runs a little longer each week. If you notice any of these signs, call (510) 201-4758 for a prompt inspection.
