Medium
D.35 on Vaillant Combi Compact 242EB

Your boiler is currently set to provide warm water only and is not attempting to heat your radiators.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

Technical description

Not relevant

DIY fix possible

Locate the heating control knob on the front panel of the boiler.Turn the dial clockwise to a higher setting to re-enable the central heating mode.Check that your room thermostat is turned up to call for heat.

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Related fault codes

D.18View →

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