Medium
E0 on Sime Murelle HE Regular

Your boiler is struggling to circulate water properly, causing the water leaving the boiler to be much hotter than the water returning to it.

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

Reduced capacity operation (∆t between delivery and return over 40°C)

From this model's manual
Verified against the Sime Murelle He Regular installation & service manual, page 32.
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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