High
S.54 on British Gas 330+

Your boiler has detected that water is not circulating properly, causing it to heat up too quickly and shut down to prevent damage.

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.

What the manual says

Manufacturer manual

waiting time: no water in system, temperature (gradient error) rise flow / return sensor too high. Check flow & return thermistor connections to pipes. Check harness connection to thermistor. Check harness wires are not trapped between any internal components.

From this model's manual
Verified against the British Gas/British Gas 330 installation & service manual, page 47.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

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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Related fault codes

F.22View →F.24View →S.53View →

All 27 fault codes on the 330+

Seeing a different code? Every code this model can display, in one place.

F3F4F5F6F10F11F13F14F15F78S.00S.02S.03S.04S.05S.06S.07S.08S.30S.32S.34S.42S.53S.76S.96S.98

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