Boiler shows E07 and will not fire, often after a power cut or wiring disturbance.
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: Isolate electrical power. Do not bypass the air pressure switch; it is a critical safety device.
User-level checks:
- Check that the flue terminal is not obstructed.
- Reset the boiler and listen for the fan starting before the error appears.
Technical checks (qualified personnel):
- Verify that the fan receives supply voltage when a heat or hot water demand is present.
- Check the fan impeller for obstruction or seizure; replace the fan assembly if noisy or not spinning freely.
- Inspect the silicone tubes to the air pressure switch for splits, blockages, or water; clear or replace as needed.
- Test the air pressure switch for correct operation with a manometer or continuity tester; replace if it does not change state with fan operation.
Once the faulty component is replaced, reset the boiler and confirm normal ignition sequence.
Repair Difficulty
Required Part
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