Medium
d8 on Remeha Avanta Plus 18s System

Your boiler has temporarily stopped because it detected that the water inside is getting hotter than the temperature you have set, likely due to poor circulation.

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

Control stop; measured flow temperature (t1) is higher than the flow temperature set (Tset flow).

From this model's manual
Verified against the Remeha/Remeha Avanta 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 fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

d9View →

All 22 fault codes on the Avanta Plus 18s System

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

89d5d9é0E01é1é2é3é4é5é6é7é8é10é11é13é43é44é45OT ERROR

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