Low
d.62 on Vaillant Home System

Your boiler is currently operating in a lower-power mode to save energy during the night or a scheduled period of reduced activity.

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.

What the manual says

Manufacturer manual

Night set-back: 0 to 30

From this model's manual
Verified against the Vaillant Home System installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

DIY fix possible

Check your external thermostat or timer settings to see if it is in 'night' or 'eco' mode.Adjust the heating schedule if you want the boiler to run at full power during this time.Wait for the scheduled period to end for the boiler to return to normal operation.

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