E125 High
Your boiler has detected that hot water is not moving around the system properly, causing it to shut down to prevent overheating.
Technical description: Primary water circulation fault
Typical repair cost: £180-450 (including labour)
DIY fix possible
Check that the boiler pressure is between 1.0 and 1.5 bar on the pressure gaugeEnsure all radiator valves are fully openCheck if any air is trapped in your radiators and bleed them if necessaryRestart the boiler by turning the selector switch to the 'R' position for five seconds
Protect yourself from future repair bills
A boiler cover plan would cover faults like E125 — no call-out fees, no surprises.
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Parts commonly replaced
- Circulation pump
- Diverter valve
- System filter (cleaning)
- Main heat exchanger (flushing)
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