What does the Vaillant d.25 fault code mean?

Your boiler is simply indicating that the 'warm start' or cylinder heating feature requested by your thermostat is currently turned off.

How much does it cost to fix Vaillant error code d.25?

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

Vaillant d.25 Fault Code: What It Means & How to Fix It

What the manual says

Manufacturer manual

Status of the requirement to reheat the cylinder or for the hot water warm start from the eBUS thermostat: off=Function deactivated, on=Function activated

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.

DIY fix possible

Check your thermostat or boiler display settings to see if the 'warm start' or 'hot water comfort' function is disabledToggle the setting to 'on' if you prefer your hot water to be kept warm for faster deliveryNo action is required if you are happy with how your hot water is currently functioning

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Related fault codes

S.27View →

All 170 fault codes on the ecoTEC Plus 840

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.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.3 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 simply indicating that the 'warm start' or cylinder heating feature requested by your thermostat is currently turned off.

What the manual says

DIY fix possible

Avoid the next call-out bill

Related fault codes

All 170 fault codes on the ecoTEC Plus 840

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