Medium
A-4 on Ferroli Arean

Your boiler has stopped providing hot water because it is having trouble reading the temperature of the water used for your taps.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

Technical description

D.H.W. sensor (42) not connected or D.H.W. temperature too high

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

A-6View →

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