From the hallway, a furnace that will not heat looks the same no matter what broke. Inside the cabinet, though, the sequence is strict: 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 Albuquerque 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
Catching these issues early helps you avoid costly problems. Here are the most common indicators that it's time to call a professional:
- Soot, rust, or moisture near the furnace cabinet or vent pipe
- Grinding or high-pitched squeals from the blower
- A bang or boom when the burners ignite late
- Short cycling every few minutes without reaching the setpoint
- The igniter glows and clicks, yet no flame ever appears
- Flames that start, last a few seconds, and go out again and again
- Air moving through the vents that never gets warm
- Yellow, wavering burner flames where they should be sharp blue
Act Before It Gets Worse
A failing capacitor, clogged condensate drain, or dirty flame sensor rarely fixes itself and usually gets more expensive to address the longer it runs. At the first hint of a problem, call (505) 209-7417 for a fast inspection.
