BoilerFaultCodesWhat the manual says
Manufacturer manualFan and pump overrun
From this model's manual
Verified against the Vaillant Ecomax 613 installation & service manual.
What causes this fault?
This status occurs because the boiler needs to remove excess heat from the internal heat exchanger after it has finished a period of heating. The fan and pump continue to run for a few minutes to safely circulate water and air, ensuring the internal components don't experience heat stress. It is a normal safety function of the system rather than a mechanical failure.
DIY fix possible
Wait 5-10 minutes for the boiler to complete its cooling cycleEnsure your thermostat or timer is still calling for heatCheck that your radiator valves are open to allow heat to dissipate
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