BoilerFaultCodesYour boiler is struggling to operate because the water pressure is too low or the water isn't moving through the system correctly.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: A flashing indicator shows lack of water or poor water circulation in central heating system.
What causes this fault?
This fault occurs when the internal sensors detect that there isn't enough water pressure or flow to safely heat the system. It is usually caused by a leak in the pipework, air trapped in the radiators, or a pump that has seized and can no longer push water around your home.
This issue often surfaces in autumn when the heating is turned back on for the first time, as pressure may have dropped during the summer months or the pump may have seized from inactivity.
DIY fix possible
Check the pressure gauge; it should ideally be between 1 and 1.5 bar.If the pressure is low, use the filling loop underneath the boiler to carefully top it up.Ensure all radiator valves are open and bleed any trapped air from your radiators.
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