E5
Worcester
Fan / Air Pressure Fault
Boiler displays E5, fan may not start or may run erratically, boiler will not ignite.
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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.
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Possible Causes
Failed Worcester fan motor, blocked or kinked air pressure switch tubes, faulty air pressure switch, flue blockage
How to Fix / Troubleshooting
Safety first: Isolate electrical power. Do not dismantle the flue unless you are a qualified engineer.
Homeowner checks:
- Check outside that the flue terminal is not obstructed by leaves, nests, or snow.
- Reset the boiler once to see if the fan starts.
Engineer checks:
- Verify the fan receives correct voltage from the PCB and that it spins freely; replace the Worcester fan assembly if seized or noisy.
- Inspect and clear the silicone tubes to the air pressure switch; ensure they are not split or blocked with condensate.
- Test the air pressure switch operation with a manometer or continuity tester.
- Check flue for internal blockage or incorrect installation causing poor draft.
Because this fault affects safe combustion, it must be rectified by a Gas Safe engineer.
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Repair Difficulty
Professional Required
5/5
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