Low
P.03 on Vaillant ecoFIT Pure 425

Your boiler is performing a routine air-bleeding or check program after being switched on or reset, and it is not currently an error that requires a repair.

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.

What the manual says

Manufacturer manual

Check programme for system without eBUS controller.

From this model's manual
Verified against the Vaillant/Vaillant Ecofit Pure 412 installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

DIY fix possible

Wait approximately 5 to 10 minutes for the program to finish automatically.Monitor the display to see if the boiler transitions to a standard temperature reading or '0' status.Ensure all radiator valves are open to help the system clear any trapped air.

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Related fault codes

P.00View →P.01View →P.02View →

All 129 fault codes on the ecoFIT Pure 425

Seeing a different code? Every code this model can display, in one place.

cond.00d.01d.02d.04d.05d.07d.08d.09d.10d.11d.13d.16d.17d.18d.20d.23d.24d.25d.27d.28d.31d.33d.34d.40d.41d.43d.45d.47d.50d.51d.58d.60d.61d.62d.64d.65d.66d.67d.68d.69d.71d.75d.77d.80d.81d.82d.83d.84d.85d.90d.93d.94D.094d.95d.96D.096F.00F.01F.10F.11F.13F.22F.23F.24F.25F.27F.28F.29F.32F.49F.61F.62F.63F.64F.65F.67F.68F.70F.71F.72F.73F.74F.75F.76F.77F.83F.85F.87F.88F.89P.00P.01P.02P.06S.01S.02S.03S.04S.05S.06S.07S.08S.20S.21S.22S.23S.24S.25S.26S.27S.28S.30S.31S.32S.34S.39S.42S.46S.53S.54S.88S.91S.96S.98S.99S.108S.109

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