From the hallway, a furnace that will not heat looks the same no matter what broke. Inside the cabinet, though, everything happens in a strict order: inducer on, pressure switch closed, igniter glowing, gas valve open, burners lit, flame proven, and finally the blower sending heat through the house. Diagnosis is mostly a matter of finding where that chain breaks. In Doral homes, it tends to be the same handful of culprits: a flame sensor coated in oxide, a hot surface igniter cracked by thermal cycling, a pressure switch held open by a tired inducer or a plugged condensate trap, or a control board with a burned relay.
When the AC quits in summer, see AC Repair.
Warning Signs for Furnace Repair
The sooner you notice these red flags, the easier and cheaper the fix. These are the signals our technicians see most often:
- Frequent on-off cycling that never reaches the thermostat setting
- Loud booms at startup caused by delayed ignition
- Burners light, run a few seconds, then shut down repeatedly
- The blower runs constantly but the air never warms
- A pilot or burner flame that is lazy yellow instead of crisp blue
- Clicking and a glowing igniter with no burner flame
- Grinding or high-pitched squeals from the blower
- Rust streaks, soot, or water around the cabinet or flue
Early Action Saves Money
Most HVAC failures start small, a weak capacitor, a squealing blower, a system that runs a little longer each week. At the first hint of a problem, call (645) 245-6089 for a fast inspection.
