BoilerFaultCodesTechnical description
Should the pressure fall below 0.5 BAR, the boiler shuts off automatically.
What causes this fault?
This fault occurs when the sealed water circuit loses its required pressure, usually due to a small leak in the pipework or at a radiator valve. It can also happen if the expansion vessel has lost its internal air charge, causing water to be forced out of the safety discharge pipe.
This issue often surfaces when you turn your heating back on for autumn, as the sudden change in temperature and pressure can highlight minor leaks that weren't visible in the summer.
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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