BoilerFaultCodesYour boiler has stopped working because the water pressure inside the 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: If the Red - Low Central Heating water pressure light flashes continually it is warning of a loss of pressure in the central heating system. During this time the red light will continue to flash and the boiler will not work.
What causes this fault?
This fault occurs when the internal water pressure drops below the minimum level required for the boiler to operate safely. The most common reasons are a slow leak from a radiator valve or pipework, or the air pressure inside the expansion vessel needs recharging. In some cases, the boiler may have simply lost pressure after you recently bled the radiators.
This issue is frequently seen in autumn when homeowners turn their heating back on for the first time, often discovering a small leak that developed while the system was idle.
DIY fix possible
Locate the external filling loop (flexible silver hose) usually under the boiler.Slowly open the small valve(s) on the loop until you hear water flowing.Monitor the pressure gauge until it reaches between 1.0 and 1.5 bar, then close the valves tightly.
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