High
d14 on Alpha E-Tec S

Your boiler is detecting a very low flow of water through your heating system, which usually means the system is blocked or the pump is struggling to circulate water.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

What the manual says

Manufacturer manual

CH flow l/h/100

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 is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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d13View →d15View →E26View →

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