Boiler shows E13; fan does not start and ignition sequence is aborted (gas models)
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 gas and electrical power. Work on combustion air and flue components only when the boiler is cool.
Steps to check:
- Inspect flue and air intake: Check outside terminals for obstructions such as leaves, nests, or ice. Clear any blockages.
- Check fan operation: With power restored briefly and a call for heat, listen for the fan. If it does not run, power back off and inspect the fan wiring and connector.
- Examine pressure switch tubing: Ensure the silicone tubes between the fan/combustion chamber and the air pressure switch are intact, not kinked, and firmly connected.
- Test pressure switch (advanced): A technician can test the switch with a manometer or continuity meter to confirm operation.
- Replace faulty components: If the fan is seized or the pressure switch does not change state, replacement is required.
When to call a technician: Combustion and flue system work must be carried out by a qualified gas technician.
Repair Difficulty
Required Part
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