BoilerFaultCodesWhat the manual says
Manufacturer manualHot–water fan over run
From this model's manual
Verified against the Vaillant Ecomax 613 installation & service manual, page 45.
What causes this fault?
This issue occurs when the boiler's internal fan fails to stop spinning after the heating cycle has finished. It is usually caused by a faulty control board sending power to the fan when it shouldn't, or the fan itself failing to report that it has slowed down correctly. Because the boiler is waiting for the 'cool down' phase to end, it will stay in this standby mode and won't start the next time you need heat.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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