Medium
E1 on Sime Murelle HE 110R

Your boiler has lost the ability to read the temperature from an external sensor, which is preventing it from heating your home properly.

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

Shorted external sensor (SE)

From this model's manual
Verified against the Sime Murelle He 110r installation & service manual, page 25.
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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