Low
d.77 on Vaillant ecoFIT Pure 435

Your boiler is notifying you that it is currently prioritising reheating your hot water cylinder at its maximum power setting.

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

Max. cylinder reheating

DIY fix possible

Wait for the hot water cylinder to reach its target temperatureCheck your hot water cylinder thermostat isn't turned up unnecessarily highOnce the water is hot, the boiler will automatically return to normal heating mode

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