Low Information
P.3 on Vaillant ecoTEC Plus 635

Your boiler is undergoing a temporary calibration process where it checks its heating settings; it is not a fault, but a normal status message.

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

Not available

What causes this fault?

This code appears when the boiler’s electronic control unit is performing a routine check of its burner and gas settings. It happens automatically to ensure the boiler is burning gas as efficiently and safely as possible. You may notice this when the boiler is first switched on or after a period of intense use.

DIY fix possible

Wait approximately 15 minutes for the program to finishEnsure your radiator valves are open to allow heat flow during the testMonitor the display to see if it returns to a standard temperature reading

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Related fault codes

P.0View →P.1View →P.2View →P.6View →

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