Low
D.84 on Vaillant Combi Compact 242EB

Your boiler is simply reminding you that a routine service is due soon based on its operating hours.

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

Maintenance indicator – number of hours until the next maintenance

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

D.80View →D.81View →D.82View →

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