BoilerFaultCodes.com
8.12 High

Your boiler has stopped working because the water pressure inside the heating system has dropped too low.

Call an engineer soon

Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description: Insufficient Water
Typical repair cost £80-150 (including labour)

DIY fix possible

Locate the filling loop, which is a silver braided hose with one or two valves connecting your boiler to the mains water supply.Open the valve(s) slowly to allow water into the system while watching the pressure gauge on the front of your boiler.Stop filling when the needle reaches the green zone, typically between 1 and 1.5 bar, then tightly close the valve(s).

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