High
D.26 on Vaillant Combi Compact 282EB

Your boiler is having trouble communicating with an internal component or external accessory, which may prevent your heating or hot water from turning on correctly.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

Additional relay control ecoTec

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

D.27View →D.28View →F.26View →

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