BoilerFaultCodes Error 19 High
Boiler Fault Code Error 19
Also written as ERROR19 — same fault.
Reviewed by the BoilerFaultCodes Editorial Team Last reviewed
Fault code Error 19 appears across 1 boiler brand and 8 models. The exact meaning varies by manufacturer — pick your boiler brand below to see the model-specific fix.
Most common meaning Your boiler has shut down because the water returning from your radiators is too hot, which suggests an issue with how the water is flowing or being measured inside the system. (As reported on Atag Q 25CR)
Pick your boiler brand for the Error 19 fix
Source
Information for the Error 19 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