Thread: microwave vent

Can't remember if I've brought this up before...

I keep running into microwave ovens over ranges where it seems like they were installed to vent to the outside, but there is no duct, so the air has nowhere to go and just kind of leaks out around the top.

I know that most if not all of them are designed to go either way, either venting outside (superior, obviously) or re-circulating inside. You change an internal baffle to set it up for one or the other.

I seems the baffle is positioned for external venting, but there's no duct.

Anyone else run into this very often?

I see it frequently, so it seems people aren't reading the installation instructions very well.

Dom.

Originally Posted by Dom D'Agostino

I see it frequently, so it seems people aren't reading the installation instructions very well.

Dom.

The ovens probably come with the baffle in the "vent outside" position, eh?

The problem with that is that grease and stuff can build up between the microwave oven and the wall behind and the cabinet above.

It is easy enough to correct as I believe all that needs to be done is to remove the microwave, and, if the blower is facing up as it was likely shipped, rotate the blower opening from facing up to facing the front; if the blower is facing the rear, the blower unit may need to be lifted up out of the top rotated 180 degrees. then lowered back into the unit, then rotated to face the front. I believe that is how it is done on GE units.

Yep, see it wrong many times. Simple fix but easy to miss if you don't check it closely.

The vent to the outside often, usually, has a hinged flap to keep prevent a cold draft. So even when the duct is installed, if the vent to indoors is open, the air will bypass the duct and blow back into the room.

A high-end range hood with two fans, one fan was dead, so air from the other fan was blowing out and blowing down on the gas burners. The flap in the duct was jammed shut.

But the cheap range hood in this last house I did had the funny setup, no duct, but with a cover over the front grill. The poor little fan is busting a gut to accomplish nothing.

Originally Posted by John Arnold

The ovens probably come with the baffle in the "vent outside" position, eh?

Seem to be shipped in "upper vent" direction. Most of the ones I see installed (both right and wrong) are GE, followed by Whirlpool.

I find about one a month, maybe more. Seems to be a pretty common goof by the homeowner or installed.

I see microwave fan venting issues alot. The last two were configured to recirculate into the kitchen. The problem was there were over sized (depth) cabinets installed that completely blocked the discharge at the upper front of the units. These were new home builder errors, not homeowner.

Jerry is correct. Simple correction. Two bolts in cabinet and hung on bracket attached to wall. 2 screws to remove and rotate blower. BUT< FOR THE NOVICE, YOU NEED 2 PEOPLE TO REMOVE MICROWAVE AND REINSTALL WITHOUT IT DROPPING ON STOVE.

Stuff happens. Always disconcerting that it wasn't picked up on installation or on first testing.

Another issue that I run into all the time is improper connection and sealing of the vent piping when it is intended to be vented to the outside. More often than not I find that there is cabinet material being used as part of the duct system.

The metal transition between the unit's outlet will be missing and there is at best a half-hearted attempted to just tape it all up from the inside. When you turn on the unit there is air leaking out between the top of the microwave and the cabinet bottom below.

I see microwave venting problems often.... I also find vent fans venting into their fancy overhead wood chase that is suppose to cover the vent pipe but they were never vented to the outside, they are just blowing into the wood chase!

Originally Posted by John Dirks Jr

I see microwave fan venting issues alot. The last two were configured to recirculate into the kitchen. The problem was there were over sized (depth) cabinets installed that completely blocked the discharge at the upper front of the units. These were new home builder errors, not homeowner.

Yes- I've seen that in new construction too. It's piece-work labor. In this area most can't read or speak English and I doubt they can read Spanish either because most everything comes with Spanish instructions.

We have mostly English speaking and a few French Canadians and they still get them installed wrong. The funniest one is the baffle they forget to take out of the box, now gone to the landfill.