BoilerFaultCodes.com
1p3 High

Your boiler has detected that water is slowly being lost from the system, preventing it from heating up safely.

Technical description: All Boilers
Typical repair cost: £80-250 (including labour)

DIY fix possible

Check the pressure gauge on the front of the boiler; it should be between 1 and 1.5 bar.Locate the filling loop (usually two small levers under the boiler) and slowly turn them to top up the pressure.Once the gauge reaches 1.5 bar, close the valves firmly and check if the error code clears.

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