The photo of the fan housing is useful. However my cover to the fan only exposes the fan, not the vent pipe like the one in the photo. I don't know how to remove the fan since the shaft turns with it and there's no way to hold the shaft due to the housing. The one in the photo may allow access to the back of the shaft but mine doesn't. From what I can see there is no blockage of the vent though. I also looked into the vent pipe from the rear and it looked clear. Is there an electronic part that might need replacing for the Moisture Sensor Control since there doesn't seem to be an air flow problem, as A.J. mentioned?