Wall-mounted air conditioners are a great solution for keeping your home cool and comfortable—especially when ductwork isn’t an option. Whether you’re upgrading an old unit or installing one for the first time, it’s important to consider a few key factors before making your choice.
Here’s a helpful guide from the team at Southern Heating & Cooling to get you started:
1. Choose the Right Type of Wall-Mounted Unit
Not all wall-mounted ACs are the same. Here are the most common types:
- Through-the-wall units (PTAC) – Self-contained systems installed directly into an exterior wall. These are common in single-room setups and are commonly referred to as “hotel units”.
- Ductless mini-splits – More advanced systems with an indoor unit mounted on the wall and an outdoor condenser. They offer zoned-control and are very efficient.
- Window-style units adapted for the wall – Less common, but some window ACs can be installed through a wall sleeve.
Each type has different strengths, so choosing the right one depends on your space, insulation, and layout.
2. Consider the Brand
Don’t let price be your only guide. A trusted, high-quality brand can make a big difference in how well the unit performs—and how long it lasts. A brand like Mitsubishi Electric is known for durability, energy efficiency, and quiet operation.
3. Match the Cooling Power to Your Space
Wall-mounted AC units are rated in BTUs (British Thermal Units). The higher the BTU rating, the larger the area it can condition. It is extremely important that the system is sized correctly for the space it will be conditioning. In the past, general guidelines based on square footage were often used to size these systems, but that is no longer the recommended method.
With houses being built much tighter and better insulated than ever before, the old guidelines often result in an oversized unit for the space. This leads to “short cycling”, which is hard on the equipment and increases electrical usage. It can also lead to humidity and odor problems.
Properly sizing the unit should be done by completing a room-by-room heat load calculation. This calculation considers a multitude of variables, such as window positions, room orientation, interior vs. exterior walls, ceiling height, and what type of structure is above and below the room itself, etc. As all of these are factors in proper sizing.
These calculations are often completed with the help of purpose-built software. If in doubt, we’re happy to help you size it right.
4. How Many Units Will You Need?
If you’re only cooling one room, a single unit might be enough. But if you’re looking to condition multiple rooms or an open-concept space, consider a multi-zone mini-split system. These setups allow multiple indoor units to be connected to a single outdoor unit—custom comfort, room-by-room.
5. Placement Matters
Where you install your AC impacts how well it works.
- Mount it high on the wall (about 6–8 inches from the ceiling) for the best airflow.
- Keep it away from heat sources, direct sunlight, and furniture that might block airflow.
- For mini-splits, outdoor unit placement matters too—somewhere with good air circulation and easy access for service.
6. Aesthetics & Design
Wall-mounted units used to be eyesores, but not anymore. Today’s systems come in sleek designs and neutral colors that blend right in. Some even offer custom covers or art panels if you want a little more personality.
7. Install It Right the First Time
We always recommend professional installation—especially for mini-splits. A properly installed unit runs more efficiently, lasts longer, and avoids costly mistakes. We often receive service calls from DIY installations where all the refrigerant has leaked out, or worse yet, the customer finds their wall wet, and the leak is now somewhere behind their sheetrock. Most DIY mini-split installs end with no warranty – so read the fine print before allowing it to be installed by someone that is not licensed. At Southern Heating & Cooling, our technicians are experienced in wall-mounted system installations.
8. Pick a Company You Trust
Your comfort depends on more than just the unit—it also depends on who installs it. Choose an HVAC company with experience, integrity, and a commitment to great service (like us!). Look for online reviews, certifications, and clear communication throughout the process.
Need Help Finding the Right Fit?
We’re here to help you choose the perfect wall-mounted AC for your home, install it correctly, and keep it running smoothly for years to come. Contact Southern Heating & Cooling today for a free consultation. We will also help you find financing and provide information on rebates that can help offset the cost of your wall-mounted air conditioner.
We’d love to help you stay cool and comfortable.