How much does it cost to fix boiler error code S.27?

Typical repair cost for the boiler S.27 fault is £0-120 including labour.

S.27 Low

Boiler Fault Code S.27

Also written as S27 — same fault.

Reviewed by the BoilerFaultCodes Editorial Team Last reviewed 27 April 2026

Fault code S.27 appears across 4 boiler brands and 63 models. The exact meaning varies by manufacturer — pick your boiler brand below to see the model-specific fix.

Most common meaning Your boiler is continuing to run the internal pump to cool down after use, which is a normal process, but it may be taking longer than usual or indicating an internal circulation issue. (As reported on Glow-worm Ultracom 2 SXI)

Pick your boiler brand for the S.27 fix

Ariston S.27 5 models Glow-worm S.27 9 models Heatline S.27 8 models Vaillant S.27 41 models

Source

Information for the S.27 fault code is sourced from the official service / installation manual for each model that displays it. Read more about how we source fault codes →

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026