BoilerFaultCodesYour boiler has stopped working because the water pressure in the central heating system has dropped too low.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Insufficient system water pressure
What causes this fault?
This fault occurs when the internal sensor detects that there is not enough water inside the system to operate safely. The most common reason is a small leak in the pipework or radiators, though it can also happen if you have recently bled your radiators and haven't topped the pressure back up.
This issue often appears at the start of autumn when the heating is turned on for the first time after summer, as seals can shrink or existing small leaks become apparent.
DIY fix possible
Locate the external filling loop, which is usually a flexible silver hose with one or two small valves.Open the valve(s) slowly to allow water into the system while watching the pressure gauge.Close the valves tightly once the gauge reaches between 1.0 and 1.5 bar, then restart the boiler.
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