Common Causes
- Dirty air filter causing the system to overheat and shut off
- Pilot light or ignitor issue
- Thermostat set incorrectly or low battery
- Tripped breaker or blown fuse
- Gas supply issue
What You Can Try
- Check that your thermostat is set to "Heat" and above room temperature.
- Replace the air filter if it hasn't been changed recently.
- Check your electrical panel for a tripped breaker.
- If the furnace still won't heat, avoid repeated restart attempts and call a technician — gas furnace issues should be diagnosed by a professional.
If these steps don't resolve the issue, stop troubleshooting and call a licensed technician — repeated restarts or DIY repairs on gas or electrical components can be unsafe.
