Venting cooking steam outside

Don't you already have an exhaust vent? Look on the outside and unlock the flapper door.

Not all convection/microwave ovens vent directly outside.
Ours does not but the range hood (separate from the microwave) does.

Download the manual and I suspect you can change it to vent to the outside. That part was easy. Had to cut through the outside and add a vent with flapper. Really dumb to have these things vent inside.

Yeah, I thought it was pretty dumb to just circulate the steam that way. There is no outside cooking exhaust vent on this RV. I thought maybe there was some hidden vent that I just hadn't found but they simply didn't build these RVs with them.

The Sharp microwave/convection oven is an all-in-one unit with a built in fan on the bottom to capture cooking steam from the range burners and, according to the installation manual I downloaded, it can be turned to either circulate or exhaust cooking steam. I'm thinking of adding the outside flapper/vent and routing the exhaust out through it. Just a little spooked about what structure or wiring might be right in the middle of a cutout. That could make for a very bad day indeed. Anyone know if a stud finder works on an RV? I think the frame on mine is steel but not sure.

Stud finders can be helpful. Go out early on a dewy morning and you may be able to see if there are beams in the way. You would not have to cut the beam out in any case. Paint it or use foam to protect it if you happen to find one in the way. I layered my two vent holes with metal duct tape. The outside plastic vent with a flap and latch was fine except no way to reach the latch. A strong magnet and then a washer glued to the inside edge works great. When the fan comes on it flaps open just fine.

our 2013 coachman marida does not have an exhaust vent for oven, VERY dumb idea.

I hadn't thought about leaving a potential wall stud in place and routing the exhaust on either side of it. Sounds like a great suggestion. I wouldn't think it would hinder much air flow, and besides anything is an improvement over gunking up the motorhome with cooking grease. Time to take the plunge and buy a vent. Thanks to all who offered help and Happy Camping!

The wall beams/studs are extruded aluminum (except in the cabin area - that is steel).
There is wiring in some places that runs in channels cut in the styrofoam in the walls.

I asked Winnebago about where some of the aluminum plates are that they put in the walls where cabinets and the like are screwed to and they emailed me drawings of the side walls showing where stuff was. You might want to give them a call.

Thanks for the suggestion. I tried my stud finder on those walls and it looks like there's a beam right in the middle of my potential cutout. I'm going to make a shallow cut inside to be sure what's behind there and route around anything in the way with the vent. I'll kill all power so there's no fireworks if I cut a wire. Going to make this happen one way or another. That cooking grease has got to go!

Done! I ordered an outside flapper vent and installed it today. I took down that huge and heavy microwave and turned around the fan to exhaust outside. The mounting bracket was still attached to the wall and it made the perfect template for marking the hole I need to cut through the wall. I made a shallow cut about 1/8" deep on the inside wall and sure enough there were two horizontal aluminum braces about 2" apart right across the area and 3 wires running vertical through it too. I decided not to cut the braces and just use the available 2" gap for the exhaust. I drilled holes through to the outside and made a shallow cut for the outside vent. The wires had enough slack so I routed them around the edge of my new vent opening. I then trimmed the new vent to fit between the braces and calked and screwed it all in place. You'd never know it wasn't "factory".

The hardest part was handling that microwave/convection oven. It was a pain taking it down and putting it back up again, but it was definitely worth the trouble. Now that cooking steam and grease will be outside instead of collecting on my walls and windows inside. I've still got to do the flapper magnet (Thanks YC 1) but that's it.

Thanks again to all who offered suggestions and Happy Camping!