How much does it cost to fix boiler error code TTB constant trip?

Typical repair cost for the boiler TTB constant trip fault is £120-450 including labour.

TTB constant trip Emergency

Boiler Fault Code TTB constant trip

Also written as TTBCONSTANTTRIP — same fault.

Reviewed by the BoilerFaultCodes Editorial Team Last reviewed 27 April 2026

Fault code TTB constant trip 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 automatically shutting down because it has detected dangerous exhaust fumes backing up into your home instead of escaping safely through the chimney. (As reported on Potterton Osprey CF 125)

Pick your boiler brand for the TTB constant trip fix

Potterton TTB constant trip 1 model

Source

Information for the TTB constant trip 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