High
2 / P on Ideal Maximiser SE

Your boiler is shutting down because it thinks the water inside is heating up far faster than it should, which often indicates a trapped air bubble or a blockage stopping the water from moving properly.

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

Temperature of safety sensor is rising too fast.

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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