BoilerFaultCodesWhat the manual says
Manufacturer manualFan not running
From this model's manual
Verified against the Worcester Bosch Greenstar 25he installation & service manual.
What causes this fault?
This fault occurs when the boiler’s safety system detects that the fan is not moving enough air to safely vent combustion gases out of the flue. The most common reasons are a build-up of dirt causing the fan to seize, a mechanical failure of the fan motor, or a fault on the main control board failing to send power to the component.
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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