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 moving heat through the ducts. Diagnosis is mostly a matter of finding where that chain breaks. In McAllen 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
Spotting the early warning signs lets you act before the problem gets expensive. Here are the most common indicators that it's time to call a professional:
- Rust streaks, soot, or water around the cabinet or flue
- Squeals, scrapes, or grinding noises behind the blower door
- Burners light, run a few seconds, then shut down repeatedly
- Clicking and a glowing igniter with no burner flame
- The blower runs constantly but the air never warms
- Loud booms at startup caused by delayed ignition
- Short cycling every few minutes without reaching the setpoint
- A flame that burns soft and yellow rather than steady blue
Early Action Saves Money
Left unchecked, even a small fault or temperature swing often signals a system working its way toward a breakdown. Don't wait, call (956) 247-0462 and we'll take a look right away.
