Low
D.70 on Vaillant Combi Compact 242EB

Your boiler is currently stuck in a diagnostic test mode used to check the internal valve that directs hot water to either your taps or your radiators.

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.

Technical description

Set diverter valve position

DIY fix possible

Turn the boiler off at the main power switchWait for 30 secondsTurn the power back on to reset the diagnostic menus

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Related fault codes

D.71View →D.72View →

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