5 Reasons Your Furnace Won't Turn On (and What to Try First)
Before you call for service, run through these quick checks — half of all 'broken furnace' calls have simple fixes.
1. The thermostat
Sounds obvious, but it's the #1 cause. Check that it's set to HEAT, the temperature is above the room temp, and the batteries are fresh.
2. The breaker
Furnaces have a dedicated breaker. Flip it fully off, then back on. If it trips again, stop — call a pro.
3. The air filter
A clogged filter can trigger a safety shutoff. Replace it and try again.
4. The power switch
Most furnaces have a switch on or near the unit that looks like a light switch. Make sure it's ON.
5. The pilot light or ignitor
Older units have a pilot light that can blow out. Newer units use an electronic ignitor that wears out every 5–10 years. Both are quick fixes for a technician.
Still not working?
Don't keep flipping the breaker or hitting reset — that can damage components. Call us, and we'll have a technician out the same day.
Have questions about your system?
Our Santa Clarita technicians are one call away.
Call (424) 552-3760Keep reading
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