High
d.24 on Vaillant ecoTEC plus System

Your boiler is signalling that the water pressure is either too low or the sensor monitoring the flow is not detecting any movement, which usually prevents the unit from starting.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

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

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

F.22View →F.75View →

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