Low
d.67 on Vaillant ecoFIT Pure 435

Your boiler is taking a planned temporary break to prevent the burner from turning on and off too frequently, which helps save energy and protect internal parts.

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

Remaining burner anti-cycling time (setting under d.02)

From this model's manual
Verified against the Vaillant Ecofit Pure 830 installation & service manual, page 31.
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

Wait for 15 to 30 minutes for the countdown to finish naturally.Check that your room thermostat is turned up higher than the current room temperature.Ensure all radiator valves are open to allow heat to move away from the boiler.

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