E9 285 High
Your boiler has shut down because it thinks the water returning to the unit is dangerously hot, which usually means water isn't circulating properly through your radiators.
Technical description: The boiler return temperature sensor has measured a temperature higher than 95°c
Typical repair cost: £120-280 (including labour)
DIY fix possible
Check that all radiator valves are fully openEnsure the boiler pressure gauge is between 1 and 1.5 barCheck that the external pump (if visible) is running and not stuck
Protect yourself from future repair bills
A boiler cover plan would cover faults like E9 285 — no call-out fees, no surprises.
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Parts commonly replaced
- Return temperature sensor (NTC)
- Circulation pump
- Main heat exchanger (flushing)
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