Low
d.24 on Vaillant ecoFIT Pure 418

Your boiler's internal water pressure sensor is checking if there is enough water flow to operate safely.

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

Status of the pressure monitor (off=Not switched, on=Switched)

From this model's manual
Verified against the Vaillant Ecofit Pure 830 installation & service manual, page 30.
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 if the water pressure on your boiler's display is between 1.0 and 1.5 barGently top up the system using the filling loop if the pressure is too lowEnsure all radiator valves and isolation valves are fully open

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Related fault codes

F.22View →F.24View →

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