Overheat lockout High
Your boiler has become too hot and has switched itself off as a safety precaution to prevent damage.
Technical description: Bleed radiators, refill system to 1.0 bar, check that radiator and boiler valves are open and reset boiler. If fault continues call an Engineer
Typical repair cost: £100-350 (including labour)
DIY fix possible
Check the pressure gauge and refill the system to 1.0 bar if it is too lowBleed all radiators to remove trapped airEnsure all radiator valves and the boiler service valves are fully openPress the 'Reset' button on the boiler display
Protect yourself from future repair bills
A boiler cover plan would cover faults like Overheat lockout — no call-out fees, no surprises.
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Parts commonly replaced
- Circulation Pump
- Overheat Thermostat
- Main Heat Exchanger (if blocked)
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