BoilerFaultCodesTechnical description
Pump over run (heating operation)
What causes this fault?
This occurs when the boiler has finished a cycle and needs to dissipate residual heat to prevent the internal components from overheating. The pump continues to circulate water through the system after the flame has gone out to ensure the heat exchanger cools down safely. It is a standard safety feature and usually indicates the system is working exactly as it should.
This status is more frequently observed during winter when the boiler is working harder and running for longer periods to heat the home.
DIY fix possible
Check that all radiator valves are not turned off at onceEnsure the bypass valve (if visible) is openWait for the boiler to finish its cooling cycle and return to normal operation
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