BoilerFaultCodes.com
12-64 High

Your boiler is having trouble managing the flame correctly and has locked itself for safety after failing to stabilise.

Technical description: Ion control deviation is too big – try resetting the boiler
Typical repair cost: £120-£350 (including labour)

DIY fix possible

Locate the reset button on your boiler's control panelPress and hold the reset button for at least 5 secondsWait for the boiler to attempt to restart; if the code returns immediately, call a Gas Safe engineer

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Protect yourself from future repair bills

A boiler cover plan would cover faults like 12-64 — no call-out fees, no surprises.

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