We have one of those built in microwave/range fan units and I've never taken it apart to really clean it down to the squirrel cage fans. It needs to come off the wall to do that and I wasn't sure if I could get it off or back onto the wall by myself, but decided to try.
It's not too bad, two bolts hold it into the cabinet above, a flange and two tabs fit into the bottom back of the cabinet, which match with a steel plate bolted to the wall. Remove bottom plate, remove top bolts, hinge downward, then lift up and off of tabs, and I can lift it away from wall.
After that there's about a dozen screws in order to get the cabinet and fan assy apart. I usually use Super Clean in a foaming bottle for regular cleaning.
The design of this is air is pulled first through two stainless mesh filters, makes a sharp 90 degree bend through a narrow passage, another 90 degree bend upwards through a wide passage, then a final 90 degree bend before hitting the squirrel cage fans. The bends and cavities give the atomized grease a lot of chances to fall out of the air.
What doesn't fall out gets to the fans, flung to the fan shroud, and eventually runs out the bottom of the shroud and into a labyrinth on one side below the shrouds. The labyrinth looks like it's meant to hold an appliance lifetime's of grease. Ours is about 20 years old and this is the first time I've taken it off the wall. The labyrinth was about half full.
The stuff that's there is a very thick syrup, and any thing that needs to be cleaned has a yellow or brown color to it. I normally use Super Clean in a foaming bottle. Frankly, it was overwhelmed by the grease. It works to about 90% but needed several attempts to get to 100%. I went through two pairs of good rubber gloves.
I scrubbed and sprayed one of the fans multiple times but I couldn't get all the stuff off until I put it into the ultrasonic cleaner. That finally took everything off. The fans are held onto the motor shafts with those one-way wavy washers; I found those easiest to remove with a large automotive pick.
Put it all back together and back on the wall. Total time: 4 hours.
It's not too bad, two bolts hold it into the cabinet above, a flange and two tabs fit into the bottom back of the cabinet, which match with a steel plate bolted to the wall. Remove bottom plate, remove top bolts, hinge downward, then lift up and off of tabs, and I can lift it away from wall.
After that there's about a dozen screws in order to get the cabinet and fan assy apart. I usually use Super Clean in a foaming bottle for regular cleaning.
The design of this is air is pulled first through two stainless mesh filters, makes a sharp 90 degree bend through a narrow passage, another 90 degree bend upwards through a wide passage, then a final 90 degree bend before hitting the squirrel cage fans. The bends and cavities give the atomized grease a lot of chances to fall out of the air.
What doesn't fall out gets to the fans, flung to the fan shroud, and eventually runs out the bottom of the shroud and into a labyrinth on one side below the shrouds. The labyrinth looks like it's meant to hold an appliance lifetime's of grease. Ours is about 20 years old and this is the first time I've taken it off the wall. The labyrinth was about half full.
The stuff that's there is a very thick syrup, and any thing that needs to be cleaned has a yellow or brown color to it. I normally use Super Clean in a foaming bottle. Frankly, it was overwhelmed by the grease. It works to about 90% but needed several attempts to get to 100%. I went through two pairs of good rubber gloves.
I scrubbed and sprayed one of the fans multiple times but I couldn't get all the stuff off until I put it into the ultrasonic cleaner. That finally took everything off. The fans are held onto the motor shafts with those one-way wavy washers; I found those easiest to remove with a large automotive pick.
Put it all back together and back on the wall. Total time: 4 hours.