What does the Vaillant P.3 fault code mean?

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

How much does it cost to fix Vaillant error code P.3?

Cost varies. Contact a Gas Safe registered engineer for a quote.

Vaillant P.3 Fault Code: What It Means & How to Fix It

What the manual says

Manufacturer manual

Not available

Shared across the range

This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s manual.

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 →

All 170 fault codes on the ecoTEC Plus 635

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

con d.00 D.000 d.01 d.02 d.04 d.05 d.06 d.07 d.08 d.09 d.10 d.11 d.13 d.14 d.15 d.16 d.17 d.18 d.19 d.20 d.21 d.22 d.23 d.24 d.25 d.27 d.28 d.31 d.33 d.34 d.35 d.36 d.39 d.40 d.41 d.43 d.45 d.47 d.50 d.51 d.58 d.60 d.61 d.62 d.64 d.65 d.66 d.67 d.68 d.69 d.70 F.00 F.0 F.01 F.1 F.10 F.11 F.12 F.13 F.20 F.22 F.23 F.24 F.25 F.27 F.28 F.29 F.32 F.33 F.49 F.61 F.62 F.63 F.64 F.65 F.67 F.68 F.70 F.71 F.72 F.73 F.74 F.75 F.76 F.77 F.78 F.83 F.84 F.85 F.86 F.87 F.88 F.89 F.91 F.92 F.97 F22 F70 P.00 P.0 P.01 P.1 P.02 P.2 P.4 P.5 P.06 P.6 P.07 S.0 S.01 S.1 S.02 S.2 S.03 S.3 S.04 S.4 S.05 S.5 S.06 S.6 S.07 S.7 S.08 S.8 S.10 S.11 S.13 S.14 S.15 S.16 S.17 S.20 S.21 S.22 S.23 S.24 S.25 S.26 S.27 S.28 S.30 S.31 S.32 S.33 S.34 S.36 S.39 S.41 S.42 S.46 S.53 S.54 S.88 S.91 S.96 S.97 S.98 S.99 S.108 S.109 T.02 T.03 T.04 T.05 T.06 T.08

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

What the manual says

What causes this fault?

DIY fix possible

Avoid the next call-out bill

Related fault codes

All 170 fault codes on the ecoTEC Plus 635

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