Wall Mounted Air Conditioners in Exterior Walls

Mike Cappuccio of N.E.T.R., Inc. talks about old-school wall mounted air conditioners, or through-wall air conditioners, why they were bad, and why modern ductless wall mounted air conditioners are a better choice.

Hi, my name is Mike Cappuccio. I’m the founder of N.E.T.R in North Andover, Massachusetts. And today I’m here to talk to you about a couple different things about wall-mounted air conditioners in your home, and some of the disadvantages of that, of a true wall-mounted air conditioner.

So, what do I mean by that? Well, a lot of people today, they still think that I can go to a big box store and buy an air conditioner, I can cut a hole in the side of my house and I can install a wall-mounted air conditioner. Well, let me tell you some of the disadvantages of that.

First, you’re not buying a wall mounted air conditioner. You’re buying a window unit most of the time. A true wall-mounted air conditioner actually goes into a sleeve that you would install in the hole that you would cut into your home. And usually the size of that hole that you would have to cut into your home would be like, say 24 to 26 inches by 18 inches. And then the sleeve would get installed. And then the big wall-mounted air conditioner would then get put into the sleeve. Well, most times, people are buying a window unit and they’re putting them into these holes.

And the disadvantage of this is, you have 2×6 construction in your home today, in these newer homes. And the discharged air through a window unit only looks to go out a window that’s one inch to two inches thick. Well, now you have a six inch wall and you’re putting in a window unit basically into your wall, and you can’t let the discharge air actually get extracted to the outside through that air conditioner that you’re putting into your wall. That’s one of the disadvantages if you’re buying a window unit to install it into your wall.

Now the second disadvantage, even if you do get an actual wall mounted air conditioner, and you install that in the sleeve, what we see and what we have seen over the past 20 years of removing hundreds of these from walls is the water usually sits in that wall mounted air conditioner over a period of time. As that’s running all summer, there’s water in that unit. And where’s that water coming from? Well, that’s the humidity that you’re removing from the space in the home. And a lot of that water, it does drip outside, but a lot of it sits in the pan in the air conditioner. And that water tends to get down inside your walls, and it starts to rot the insides of your walls out. It rots the sills out inside the home which the air conditioner is sitting on top of.

And by the time we actually come 15, 20 years later to remove that, the unit is actually shaking inside the wall. The wall is all rotted, and there’s usually not just [an option to] remove it at that time and patch it. There’s usually major construction that needs to be done with that wall. And the mold sometimes that you see in there, it’s just awful. So now you need mold remediation as well.

So let me talk to you now about some of the advantages of a wall mounted air conditioner that is basically a ductless wall mounted air conditioner. That can be installed on an exterior wall or an interior wall for that [matter].

So, I’m going to talk to you a little bit about the exterior wall first, and how they actually go onto the wall. The actual unit would mount onto the wall. There’s a backing plate. There’s not a 2 foot by 18 inch hole that needs to be opened up in your home. It’s basically a little 3 inch hole that gets cut on usually the bottom right hand corner of the unit, or the bottom left hand corner of the unit. Most of the time, the right, though. And the hole gets sleeved, and the pipes, drains, and electrical then would just be pushed to the outside. And on the exterior of the home, some line hide would be put on there. And the piping refrigerant line and electrical would run down to an outdoor condenser, if you were to install that on your exterior wall of your home.

Now these wall mounted air conditioners from Mitsubishi Electric can also be installed on interior walls as well. We do this every day. It’s a regular occurrence, and there’s a few different ways you can do it. A lot of times you have a bedroom or a room that you might have a closet near that we can mount on an interior wall, and then take the piping, electrical, and drains and put them in line hide in the closet, usually in the back corner of a closet. And then run the piping down into a basement or crawl space. And from there, you can run the piping anywhere you want to go from there. You run it across the basement, run it to the outside and bring it to the condenser.

A lot of times we’ve even put the piping inside the walls of a home because all your interior walls are hollow. They’re usually not insulated unless you’re in a sound studio or something like that. And these hollow walls are very easy to get up into from the basement, and run the piping right inside them, and bring the piping down into the basement or a crawl space, whatever’s under there. And then run those lines out to the condensing unit that would then be placed outside the home. So there’s a lot of different ways to actually install these in homes. Like I said, you can use the interior wall or the exterior wall. Either one will work. So please feel free to check out our website or give us a call. Our in-home consultations, they can explain to you exactly how this will be done. But please, before you cut a 2 foot by 18 inch hole in your home, please, please give us a call and look at the other options. Because I think you’re going to see that in time, this is a good choice, and the right way to do things in your home.