Low
P.1 on Vaillant ecoTEC

Your boiler is currently running a self-diagnostic test at maximum power to ensure everything is working correctly after ignition.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

Technical description

Test program where the appliance is operated in full load after successful ignition

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

P.0View →P.2View →

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