Furnace does not start; LED flashes seven times repeatedly; blower may run continuously.
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
Critical safety warning: A flame rollout condition can indicate a dangerous combustion problem and potential carbon monoxide hazard. If rollout switches are tripped, shut off gas and power and contact a licensed HVAC technician. Do not bypass or jumper rollout switches.
- Visual inspection only: With power off, remove the burner access panel and look for signs of overheating: scorched paint, melted wires, or soot around the burners.
- Check rollout switches: Locate the rollout switches near the burner area. Some have manual reset buttons; if accessible, press gently to reset. If they immediately trip again on startup, stop and call a professional.
- Do not attempt DIY heat exchanger repair: Cracked or blocked heat exchangers require professional diagnosis and often furnace replacement.
Repair Difficulty
Required Part
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