High
P1 on Vaillant Thermocompact

Your boiler is currently running at its maximum gas setting, which is usually a sign that it is trying to heat up quickly or has detected an internal issue with the gas flow control.

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

Full gas rate

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

P2View →

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