BoilerFaultCodesTechnical description
Pump stuck or running with air in the system
What causes this fault?
This fault occurs when the boiler's internal pump is unable to circulate water because it is physically jammed or there is a large pocket of air preventing it from gaining traction. Over time, debris in the system water can seize the pump's moving parts, or air can enter the system after a period of inactivity or a recent repair.
This fault is more common in autumn when homeowners turn their heating back on for the first time, as pumps often seize after being idle throughout 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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