High
0 / Y on Ideal Maximiser SE

Your boiler is struggling to direct heat to your radiators while potentially making your hot water tank dangerously hot.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

The unit switches off at the central heating side or feeds back power on the supply sensor. The central heating installation is not heated, the hot water tank (if present) is overheated.

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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