Medium
d17 on Alpha E-Tec NXS

Your boiler is struggling to accurately read or control the temperature of the water circulating through your radiators.

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

Calculated flow temperature

From this model's manual
Verified against the Alpha E Tec Nxs installation & service manual, page 33.
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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