BoilerFaultCodesTechnical description
High pressure – circulating pump failure orcircuit air locked
What causes this fault?
This fault occurs when water is unable to flow freely through the boiler, leading to a sudden rise in internal pressure. The most common reason is a failed circulating pump that can no longer push water around your radiators, or a large pocket of air trapped within the pipework that is acting as a physical blockage.
This issue is frequently seen in autumn when heating systems are turned back on after being idle all summer, which can cause the internal pump to seize.
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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