High
U2453 on Grant Vortex Blue

Your boiler's electronic control system has encountered a communication error or internal memory fault, likely requiring a professional software reset or control board inspection.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

Fault U: Network CodeProblem is climate control system, lighting, airbags, etc..fault two; MFG – Manufacturer Specificfault four; Transmissionfault five; TP Sensor Learn Not Completefault three; Transmission Control Module Reprogrammable Memory

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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