Ideal boiler displays L2 and will not fire, often after a failed ignition attempt
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 the boiler if you suspect flue damage or smell fumes. Do not use the boiler until checked by a Gas Safe engineer.
User checks:
- Check condensate pipe (especially in cold weather): If the white plastic condensate pipe runs outside, it may be frozen or partially blocked. See the L2/condensate guidance below.
- Reset the boiler: After addressing any obvious condensate issue, reset the boiler once and observe.
- Check flue terminal: Ensure the external flue terminal is not blocked by debris or snow.
Condensate thawing (if frozen):
- Turn off the boiler.
- Locate the external section of the condensate pipe (usually 21.5mm or 32mm white plastic).
- Pour warm (not boiling) water along the pipe to gently thaw it.
- Once thawed, reset the boiler.
If L2 persists, a Gas Safe engineer must inspect the flame sensor, burner, gas valve, and flue system.
Repair Difficulty
Required Part
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