BoilerFaultCodes No HW but CH OK Medium
Boiler Fault Code No HW but CH OK
Also written as NOHWBUTCHOK — same fault.
Reviewed by the BoilerFaultCodes Editorial Team Last reviewed
Fault code No HW but CH OK appears across 1 boiler brand and 1 models. The exact meaning varies by manufacturer — pick your boiler brand below to see the model-specific fix.
Most common meaning Your boiler is comfortably heating your home, but a specific internal component is failing to divert heat to your hot water tank. (As reported on Ideal Icos System)
Pick your boiler brand for the No HW but CH OK fix
Source
Information for the No HW but CH OK 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