Medium
E1 on Sime Murelle HE Regular

Your boiler's external temperature sensor is sending an incorrect electrical signal, likely due to a loose wire or a faulty sensor unit, preventing the system from regulating the temperature correctly.

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)

Shared across the Murelle HE 35 R range
This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s 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

E2View →

All 34 fault codes on the Murelle HE Regular

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

ALL 02ALL 05ALL 06ALL 07ALL 08ALL 09ALL 13ALL 14ALL 15ALL 21ALL 22ALL 23ALL 24ALL 25ALL 26ALL 27ALL 28ALL 29ALL 30ALL 31ALL 32ALL 33ALL 34ALL 35E0E2E3E4E5E6E7E8E9

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