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 Glens Falls, NY, 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. Each one halts the startup, and from the hallway they all look alike.
When the AC quits in summer, see AC Repair.
Warning Signs for Furnace Repair
Recognizing the warning signs early can save you time and money. Watch for these telltale signs:
- A fan that keeps running while the registers blow cool air
- Soot, rust, or moisture near the furnace cabinet or vent pipe
- Yellow, wavering burner flames where they should be sharp blue
- Booming or banging at light-off from delayed ignition
- Squealing or grinding from the blower compartment
- The igniter glows and clicks, yet no flame ever appears
- Repeated shutdowns just seconds after the burners light
- Short cycling every few minutes without reaching the setpoint
Early Action Saves Money
Most HVAC failures start small, a weak capacitor, a squealing blower, a system that runs a little longer each week. Don't wait, call (518) 201-6286 and we'll take a look right away.
