Landlords and homeowners alike have an interest in keeping their spaces cool to keep tenants and their own families happy and comfortable.
Central air conditioners cool the house using one system for the whole house or for each floor, and they require ductwork, something that might not be possible in homes that don't have enough space between floors or under the house.
Enter wall and window units, the option of choice for efficient, affordable cooling for homes without central air and to supplement it in some homes where central air also exists, such as in finished rooms over garages.
Here's a quick look at window and wall units.
How they're the same
Window and wall air conditioners are intended to cool one room at a time, or perhaps to cool two smaller rooms at the most. If there are separate rooms, the room without the unit is likely to be the warmer, since the thermostats are typically on the units themselves, surrounded by the cooled air coming out of the unit.
Either way, most come with different modes, such as a cooling mode that takes the air in the room, lowers its temperature, and sends it back into the room, and then a fan-only option that saves energy by moving air without cooling it.
Unlike central HVAC systems' wall-mounted thermostats, window and wall units regulate the temperature with built-in thermostats.
How they differ
Wall air conditioners are just that. They're units that are installed through an exterior wall. Inside, wall units can be easier to decorate around or otherwise obscure, and they don't block the view.
Window units take up window space and to many, don't look as clean or permanent, especially from the inside. But they are easier to install since they sit in an existing hole: the window.
Either choice is a good bet for easy cooling solutions, says this blog from Total Home Supply, which adds, "For more of a short-term solution, window units can be a solid option since they're cheaper and tend not to last as long."
"On the flip side, through-the-wall air conditioners can be better long-term options, as they are more permanently installed and last longer. They're also easy to replace since an existing sleeve is already installed when the need for a new unit comes."
In addition, while they may cost more because of the installation required, an in-wall unit may make up that difference in the long run in energy savings. Because properly installed, they're sealed better than window units, meaning they use less electricity, a significant plus for landlords who pay for that utility.
Once decided, now to choose
Once you decide between wall or window, the next choice is the unit itself. The manufacturers will provide recommended cooling spaces for each of their units, but you can also follow this online guide from Lowe's, which compares room sizes to the BTU rating needed to cool that space with their window units.
BTU means British thermal unit, a measure of how much heat is removed from the room. The higher the rating, the higher the cooling power.
Prices vary depending on features and power, such as electronic or manual controls, sleep settings, dehumidifying capabilities, and available electronic ionizers designed to help remove pollen and other impurities from the incoming air.
As for how much, HowMuch.net pegs the average cost of a wall-mounted unit at $1,349 for a 340-square-foot room. That's 20 feet by 17 feet, a nice-sized space. Of that, $856 is for the unit itself. Meanwhile, a quick search finds an LG window air conditioner designed to cool the same 340 square feet at about $300. A significant difference, but having the window unit installed -- for those uncomfortable working with a heavy item, especially from a second-floor window -- would add to the cost.
Wall and window units are each designed to serve a certain consumer's taste. If you're looking for a lower-cost, short-term solution for a small space, go with the window unit. If you need something that's going to last and would prefer that it looks like it's a part of the room, rather than a clunky addition, then the wall unit may be for you.