Medium
Er07 on Biasi ActivA 18S

Your boiler is having trouble measuring the temperature of your hot water, which means it cannot heat it correctly.

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.

What the manual says

Manufacturer manual

Faulty d.h.w. temperature probe NTC

From this model's manual
Verified against the Biasi Activa 18s installation & service manual, page 12.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

Engineer required

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

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