Medium
ALL 03 on Sime Murelle HE System

Your boiler's internal water pressure is currently too high, which is preventing it from operating safely.

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

HIGH SYSTEM PRESSURE

From this model's manual
Verified against the Sime Murelle He System installation & service manual, page 28.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

DIY fix possible

Locate a radiator in your home that has a bleed valve.Place a cloth and a container underneath the valve to catch water.Open the bleed valve slowly to release air and water until the pressure gauge on the boiler drops to between 1 and 1.5 bar.Close the valve tightly and check the boiler display to see if the error has cleared.

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