Medium
03 on Sime Murelle EV HE Combi

Your boiler has detected that the water pressure in your heating system is too high for it to operate 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 Ev He Combi installation & service manual, page 31.
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 with a bleed valve.Place a cloth and a container underneath the valve.Open the bleed valve slightly to release a small amount of water until the pressure gauge on your boiler drops to the green zone (typically 1.0 to 1.5 bar).Close the valve securely.

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