Medium
117 on Potterton Promax Ultra Combi ErP

Your boiler has detected that there is too much water pressure inside the system, which can cause it to stop working to prevent internal damage.

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

Primary System Water Pressure Too High

From this model's manual
Verified against the Potterton Performa 24i He installation & service manual, page 47.
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 or small container under the valve.Open the valve slightly to release air and a small amount of water until the pressure gauge on the boiler drops to between 1.0 and 1.5 bar.

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Related fault codes

E117View →E118View →

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