Medium
d.41 on Heatline Vizo 28

Your boiler is struggling to detect the temperature of the water returning from your radiators, which means it may not be heating your home as efficiently as it should.

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

Heating return temperature

From this model's manual
Verified against the Heatline Capriz Plus installation & service manual, page 25.
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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Related fault codes

d.40View →d.42View →

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