E.01 – .20 High
Your boiler has switched itself off because it has become too hot inside, likely due to water not flowing correctly or a faulty internal sensor.
Technical description: Maximum flue gas temperature reached. No circulation or sensor fault.
Typical repair cost: £120-350 (including labour)
DIY fix possible
Check that your home's radiator valves are fully openEnsure your system pressure is between 1 and 1.5 bar on the pressure gaugeTry resetting the boiler by turning the selector switch to 'R' for five seconds
Protect yourself from future repair bills
A boiler cover plan would cover faults like E.01 – .20 — no call-out fees, no surprises.
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Parts commonly replaced
- Flue Overheat Thermostat
- Main Heat Exchanger
- Circulation Pump
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