Furnace starts and runs for a few minutes, then shuts off and restarts repeatedly.
Safety Warning
This repair may involve working with high voltage components or water connections. Always unplug the appliance before removing any panels.
If you are not confident in your ability to perform this repair safely, we strongly recommend contacting a professional technician.
Possible Causes
How to Fix / Troubleshooting
Safety first: Turn off power before accessing internal components.
Step-by-step checks:
- 1. Replace air filter: Install a new filter to restore airflow.
- 2. Check vents and returns: Open all registers and returns. Remove obstructions.
- 3. Inspect evaporator coil (if A/C installed): Above many Philco furnaces is an A-coil. If accessible, check for heavy dust or ice. A dirty coil can severely restrict airflow and cause limit trips. Cleaning is best done by a professional.
- 4. Listen to blower: If the blower sounds weak or slow, the motor may be failing.
When to call a professional: A technician should measure temperature rise across the furnace, inspect the coil, and test blower motor amperage. They may adjust blower speed or recommend duct modifications.