Low
P.12 on Vaillant aquaPLUS

Your boiler is undergoing a temporary waiting process while it determines if the water pressure is high enough to run safely.

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 applicable - for GB

DIY fix possible

Check the pressure gauge on the front of the boiler.If the pressure is below 1.0 bar, use the filling loop handles to top it up to 1.5 bar.Restart the boiler once the pressure is correct.

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