High
15E on Biasi Activ A

Your boiler is struggling to circulate water properly, which is preventing it from heating your home or water safely.

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

None or too low water flow; Faulty pump (temp. difference between probes higher than 35° C)

From this model's manual
Verified against the Biasi/Biasi Bm Biasi Concept 400 20 1 Mfs installation & service manual.
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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Related fault codes

15EView →E15View →

All 31 fault codes on the Activ A

Seeing a different code? Every code this model can display, in one place.

01E02E03E04E05E06E08E09E10E11E14E16E17E18EErEr 01Er 02Er 03Er 04Er 05Er 06Er 08Er 09Er 10Er 12Er 14Er 15Er 16Er 17Er 18

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