Low Information
P.1 on Vaillant ecoTEC exclusive

Your boiler is currently running a self-test at maximum power to ensure everything is working correctly after it has started up.

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 programme where the appliance is operated in full load after successful ignition.

What causes this fault?

This isn't actually a fault, but rather a temporary status code triggered when the boiler is performing a safety and performance check. After ignition, the control system forces the boiler to run at its highest power setting to verify that the gas valve and fan are operating correctly. Once the internal sensors are satisfied that the burner is stable at full capacity, the code will disappear and the boiler will return to normal operation.

DIY fix possible

Wait for the test to complete automaticallyMonitor the display to see if it returns to its normal temperature readingIf the code persists for more than 15 minutes, try restarting the boiler

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Related fault codes

P.0View →P.2View →P.6View →

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