Set Appliance State:

Isolate Mains Power to appliance as per TOPs P4
Remove the air intake duct from the fan assembly

Observation:

Visually inspect the air intake on the fan assembly.
It should be clear of any restrictions or blockages, pay particular attention to the 4 venturis inside the air intake as highlighted by the arrow.
Note:
The fan does not need to be removed to carry out this inspection as it is possible with a torch and mirror.
Is the fan intake in good condition and clear of any restrictions or blockages?
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