BoilerFaultCodesTechnical description
The water pressure is less than 0.5 bar. Check the water pressure and top up the system
What causes this fault?
This fault occurs when the internal sensors detect that there isn't enough water volume to safely transfer heat around your home. The most common reason is a slow leak in the radiator network or pipework, but it can also happen if you recently bled your radiators without topping up the pressure afterwards.
This issue often surfaces when you turn the heating back on for autumn, as the system settles after being dormant or develops leaks from expanding and contracting metal.
Engineer required
This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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