BoilerFaultCodesTechnical description
Fault on Pump or Low System Pressure
What causes this fault?
This fault occurs when the boiler's internal sensors detect that water isn't moving through the heat exchanger as it should, which can cause the unit to overheat. The most common reasons are that the water pressure has dropped too low for the system to operate, or the internal pump has seized or failed. Occasionally, a large air bubble trapped inside the pipework can also block the flow and trigger this error.
This issue is frequently seen in autumn when the heating is turned back on for the first time, as pumps can seize after being idle over 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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