High
d9 on Remeha Selecta

Your boiler has switched itself off because the water inside is heating up too quickly or too unevenly, which often happens when water cannot circulate through your radiators properly.

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

Shut down; maximum temperature rise is exceeded or if the dT between the supply and return temperature ≥ 45°C or a rate of rise in the flow temperature > 1°C/sec.

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 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

E04View →E05View →

All 22 fault codes on the Selecta

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

89d5d8é0E01é1é2é3é4é5é6é7é8é10é11é13é43é44é45OT ERROR

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