BoilerFaultCodesWhat the manual says
Manufacturer manualWater pressure too high - You have put too much water pressure in your system
From this model's manual
Verified against the Keston/Keston C36p installation & service manual, page 32.
DIY fix possible
Locate a radiator in your home, preferably one upstairs.Use a radiator bleed key to gently open the bleed valve.Release a small amount of water into a cloth or container until the pressure gauge on the boiler front drops to between 1 and 1.5 bar.Close the valve and check the boiler display to see if the error clears.
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Related fault codes
All 29 fault codes on the C36p
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