Low
d17 on Alpha E-Tec S

Your boiler is simply displaying the current temperature of the water flowing through your heating system as part of its standard diagnostic readout.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

What the manual says

Manufacturer manual

Calculated flow temperature °C

From this model's manual
Verified against the Alpha E Tec S 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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