Furnace fails to start or shuts down with F5, fan may run continuously, no heat
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 heat exchanger or venting problem that can lead to fire or carbon monoxide. Do not repeatedly reset rollout switches without finding the cause. If you suspect a cracked heat exchanger or smell exhaust, shut the system down and call a qualified gas engineer immediately.
Steps (visual only):
- Turn off power and gas: Isolate the furnace completely.
- Inspect rollout switches: Locate the small manual-reset rollout switches around the burner area on your Ideal furnace. If a red button is popped, it has tripped. Do not reset until a technician has inspected the furnace.
- Check for obvious blockages: Look for heavy soot, debris, or signs of overheating around the burner compartment. Do not operate the furnace if you see these signs.
- Call a professional: A qualified technician must inspect the heat exchanger, burners, and flue system, clean as needed, and verify safe combustion before resetting or replacing rollout switches.
Repair Difficulty
Required Part
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