BoilerFaultCodes P37 Medium
Boiler Fault Code P37
Reviewed by the BoilerFaultCodes Editorial Team Last reviewed
Fault code P37 appears across 1 boiler brand and 2 models. The exact meaning varies by manufacturer — pick your boiler brand below to see the model-specific fix.
Most common meaning Your boiler is receiving an invalid or missing control signal from an external device, such as a smart thermostat or building management system, preventing it from heating correctly. (As reported on Alpha Pro Tec Plus)
Pick your boiler brand for the P37 fix
Source
Information for the P37 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 7 July 2026