High
PP3 on Grant Vortex Blue

Your boiler's internal thermometer has stopped working correctly, meaning the system can no longer safely monitor its own temperature to provide heating.

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

Coil temperature sensor failure

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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Related fault codes

PP1View →PP2View →PP4View →

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