Medium
ALL 03 on Sime Murelle Elite HE Combi

Your boiler has detected that the water pressure inside 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 ALARM

From this model's manual
Verified against the Sime Murelle Elite 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, preferably on the ground floor.Place a cloth or small container under the radiator bleed valve.Slowly open the valve to release water until the pressure gauge on the boiler shows between 1 and 1.5 bar, then tighten the valve firmly.

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