Low
E2 on Sime Murelle HE Regular

Your boiler is simply letting you know that it is currently warming up its internal water supply to ensure hot water is ready for you as soon as you turn on the tap.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

What the manual says

Manufacturer manual

Preheating function active

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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