BoilerFaultCodes.com
1p4 High

Your boiler has detected that water is circulting too slowly or there is not enough water pressure to run safely.

Technical description: Clas Net one CombiClas one CombiClas System one
Typical repair cost: £0-280 (including labour)

DIY fix possible

Check the pressure gauge on the front of the boiler; it should be between 1 and 1.5 bar.If the pressure is too low, use the filling loop underneath the boiler to top it up carefully.Ensure all radiator valves are fully open and check for any visible leaks around the pipework.

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