Low
d15 on Alpha E-Tec Plus 10 / 18

This code is just a status update showing your boiler's internal fan speed, rather than an error that requires immediate action.

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

Fan speed during current operation rpm/100

From this model's manual
Verified against the Alpha E Tec Plus 10 18 installation & service manual, page 30.
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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