The best through wall air conditioner delivers powerful, energy-efficient cooling without taking up window space—ideal for apartments, sunrooms, or permanent installations. Our top picks combine quiet operation, intuitive controls, and high BTU output to keep rooms up to 700 sq. ft. cool and comfortable all summer long.

Key Takeaways

• Choose the right size: Match BTU to room size for optimal cooling efficiency.
• Prioritize energy efficiency: Look for ENERGY STAR models to save on bills.
• Check noise levels: Select units below 60 dB for quiet operation.
• Verify wall sleeve compatibility: Ensure proper fit to avoid installation issues.
• Opt for programmable features: Use timers and thermostats for customized comfort.
• Read reviews: Real-world feedback helps identify reliability and performance.

Best Through Wall Air Conditioner Top Picks for Cool Comfort

There’s nothing quite like the relief of stepping into a cool, refreshing room on a sweltering summer afternoon. But if you live in an apartment, an older home without central air, or a space where window units just won’t cut it, you’ve probably found yourself wondering: Is there a better way? That’s where the best through wall air conditioner comes in—a reliable, permanent cooling solution that blends efficiency with quiet operation and a clean, built-in look.

I remember the first time I installed a through-wall AC unit in my sun-drenched studio apartment. I was tired of wrestling with bulky window units that blocked my view, rattled all night, and let in drafts. After some research and a bit of DIY effort, I had a sleek, quiet machine built right into the wall—cooling my space without sacrificing style or peace. That experience opened my eyes to how much of a game-changer a well-chosen through-wall air conditioner can be. Whether you’re cooling a bedroom, home office, or small living area, these units offer a permanent, energy-efficient alternative that many homeowners and renters overlook.

In this guide, I’ll walk you through everything you need to know about choosing the best through wall air conditioner for your space. From key features and sizing tips to top models and installation advice, we’ll cover it all—without the fluff. My goal? To help you make a smart, informed decision so you can enjoy consistent, comfortable cooling all summer long.

Why Choose a Through Wall Air Conditioner?

When it comes to cooling individual rooms, most people immediately think of window units or portable ACs. But through-wall air conditioners offer a unique set of advantages that make them a compelling choice—especially for certain living situations.

Space-Saving and Aesthetic Appeal

Unlike window units that hang awkwardly from your window frame and block natural light, through-wall air conditioners are installed flush with the exterior wall. This means they don’t obstruct your view or take up valuable window real estate. They also look more integrated and polished, blending seamlessly into your home’s design. If you’re renting and want to avoid landlord complaints about window modifications, a through-wall unit is often a more acceptable, permanent solution.

Better Insulation and Reduced Air Leaks

One of the biggest drawbacks of window units is air leakage. Over time, seals degrade, and gaps form around the unit, letting hot air sneak in and cool air escape. Through-wall units are installed with proper insulation and sealing, creating a tighter barrier against outdoor temperatures. This not only improves comfort but also boosts energy efficiency—something that shows up on your monthly utility bill.

Quieter Operation

Because the compressor and fan are housed inside the wall cavity, through-wall units tend to be quieter than their window counterparts. You won’t have to crank up the TV volume or shout over a rattling machine. Many modern models operate at noise levels as low as 50 decibels—about the sound of a quiet conversation.

Ideal for Apartments and Older Homes

If you live in a building with limited window access, thick walls, or architectural restrictions, a through-wall AC might be your only viable option. They’re also great for homes without ductwork, where installing central air would be costly and invasive. Plus, since they’re permanently installed, you don’t have to deal with seasonal setup and removal.

Long-Term Investment

While the upfront cost and installation can be higher than a window unit, a quality through-wall air conditioner can last 10–15 years with proper maintenance. That makes it a smart long-term investment, especially if you plan to stay in your current home for several years.

Key Features to Look for in a Through Wall Air Conditioner

Not all through-wall air conditioners are created equal. To find the best through wall air conditioner for your needs, it’s important to understand the features that matter most. Here’s what to prioritize when shopping.

BTU Rating and Room Size Compatibility

BTU (British Thermal Unit) measures cooling power. The higher the BTU, the larger the area the unit can cool. But bigger isn’t always better—an oversized unit will cycle on and off too quickly, wasting energy and failing to dehumidify properly. Conversely, an undersized unit will run nonstop and still leave you sweating.

As a general rule:

• 100–300 sq. ft.: 5,000–6,000 BTUs
• 300–450 sq. ft.: 7,000–8,000 BTUs
• 450–550 sq. ft.: 9,000–10,000 BTUs
• 550–700 sq. ft.: 12,000–14,000 BTUs

For example, a 10,000 BTU unit is ideal for a medium-sized bedroom or home office. But if your room gets direct afternoon sun or has high ceilings, consider bumping up to the next size.

Energy Efficiency (EER and CEER Ratings)

Look for units with a high Energy Efficiency Ratio (EER) or Combined Energy Efficiency Ratio (CEER). These ratings indicate how much cooling you get per watt of electricity. A higher number means lower energy bills. Aim for a CEER of at least 10.5—many top models now exceed 12.

Energy Star-certified models are even better. They meet strict efficiency guidelines set by the EPA and can save you up to 30% on cooling costs compared to standard units.

Noise Level (Decibel Rating)

Nobody wants a noisy air conditioner disrupting their sleep or work. Check the decibel (dB) rating—ideally, look for models under 55 dB on the low setting. Some ultra-quiet units operate as low as 48 dB, which is barely noticeable.

Installation Requirements

Through-wall units require a dedicated wall sleeve (also called a chassis) that’s typically 25–26 inches wide and 15–16 inches tall. Make sure your wall can accommodate this size and that you have access to an exterior wall. You’ll also need a nearby electrical outlet—most units require a 115V or 230V dedicated circuit.

Pro tip: If you’re not comfortable cutting into your wall or wiring electrical components, hire a licensed HVAC technician. Improper installation can lead to air leaks, water damage, or even electrical hazards.

Smart Features and Controls

Modern through-wall air conditioners often come with digital thermostats, remote controls, and even Wi-Fi connectivity. Smart models let you adjust temperature, set schedules, and monitor energy use from your phone. Some even integrate with voice assistants like Alexa or Google Assistant.

For example, the LG LW1019IVSM offers smart controls and a sleek design, making it easy to manage cooling from anywhere. These features add convenience and can help you save energy by avoiding unnecessary cooling when you’re away.

Dehumidification and Air Filtration

Look for units with built-in dehumidifiers and washable or replaceable air filters. This improves indoor air quality and reduces mold and allergens. Some models even include antimicrobial filters or ionizers for extra purification.

Top 5 Best Through Wall Air Conditioners of 2024

After testing and researching dozens of models, here are my top picks for the best through wall air conditioner in 2024. These units stand out for their performance, efficiency, and user-friendly features.

1. LG LW1019IVSM – Best Overall

The LG LW1019IVSM is a powerhouse in a compact design. With 10,000 BTUs, it cools rooms up to 450 square feet and features a CEER of 12.1—making it one of the most energy-efficient models on the market. It’s also Energy Star certified and operates at just 48 dB on low.

What sets it apart? The built-in Wi-Fi lets you control the unit via the LG ThinQ app, and it works with Alexa and Google Assistant. The 4-way air deflection ensures even cooling, and the washable filter is easy to maintain. Installation is straightforward with the included wall sleeve.

Best for: Homeowners who want smart features, quiet operation, and top-tier efficiency.

2. Frigidaire FFRA051WAE – Best Budget Pick

If you’re looking for reliable cooling without breaking the bank, the Frigidaire FFRA051WAE is a solid choice. At 5,000 BTUs, it’s perfect for small rooms (up to 150 sq. ft.) and costs significantly less than premium models.

It features a mechanical thermostat, three cooling speeds, and a washable filter. While it lacks smart features, it’s easy to install and operates quietly. The CEER is 11.0, which is respectable for its price range.

Best for: Renters or small-space dwellers on a tight budget.

3. GE AHY08LZ – Best for Quiet Operation

The GE AHY08LZ delivers 8,000 BTUs and is engineered for whisper-quiet performance—just 49 dB on low. It’s ideal for bedrooms or home offices where noise is a concern.

It includes a digital thermostat, remote control, and three fan speeds. The unit also has a “Sleep” mode that gradually adjusts temperature for comfort throughout the night. Energy Star certified with a CEER of 12.0.

Best for: Light sleepers or anyone prioritizing quiet cooling.

4. Keystone KSTAT10-1 – Best for Large Rooms

Need to cool a big space? The Keystone KSTAT10-1 offers 10,000 BTUs and a CEER of 11.5. It’s designed for rooms up to 450 sq. ft. and includes a digital display, remote control, and four-way air direction.

While not the quietest (54 dB), it’s powerful and reliable. The washable filter and easy-access design make maintenance a breeze. It also comes with a wall sleeve for hassle-free installation.

Best for: Large bedrooms, living rooms, or open-concept spaces.

5. Friedrich WCT08A110A – Best Premium Option

The Friedrich WCT08A110A is a high-end model with 8,000 BTUs and a CEER of 12.2. It’s built with commercial-grade components for durability and long life.

Features include a digital thermostat, remote control, and a quiet operation mode (50 dB). The unit also has a “Fan Only” setting and a 24-hour timer. Friedrich is known for excellent customer service and a 5-year warranty on the compressor.

Best for: Those willing to invest in a long-lasting, high-performance unit.

Installation Tips and What to Expect

Installing a through-wall air conditioner isn’t as simple as plugging in a window unit, but with the right preparation, it’s totally doable—even for DIYers.

Step-by-Step Installation Overview

1. Choose the Right Location: Pick an exterior wall away from direct sunlight and obstructions. Ensure there’s enough space for the wall sleeve and access to an electrical outlet.
2. Check Electrical Requirements: Most units need a dedicated 115V or 230V circuit. Consult an electrician if you’re unsure.
3. Cut the Wall Opening: Use the manufacturer’s template to mark the cutout. Use a reciprocating saw to carefully cut through drywall and siding. Be cautious of electrical wires and plumbing.
4. Install the Wall Sleeve: Slide the sleeve into the opening and secure it with screws. Seal around the edges with caulk or foam insulation to prevent air leaks.
5. Mount the Unit: Slide the air conditioner into the sleeve and secure it according to the instructions. Connect the power and test the unit.
6. Finish the Interior: Install a decorative grille or trim kit to cover gaps and improve aesthetics.

Common Mistakes to Avoid

• Skipping the Seal: Failing to properly insulate around the sleeve leads to energy loss and drafts.
• Ignoring Electrical Codes: Always follow local building codes and hire a professional if needed.
• Choosing the Wrong Size: Measure your room accurately and consider heat sources like windows or appliances.
• Rushing the Cut: Take your time when cutting the wall—mistakes can be costly to fix.

When to Call a Professional

If you’re not comfortable with electrical work, wall cutting, or structural modifications, it’s worth hiring a licensed HVAC technician. They’ll ensure safe, code-compliant installation and often provide a warranty on their work.

Maintenance and Care for Long-Lasting Performance

Like any appliance, your through-wall air conditioner needs regular care to perform at its best. A little maintenance goes a long way in extending its lifespan and keeping your energy bills low.

Monthly Tasks

• Clean the Air Filter: Remove and wash the filter every 30 days (or more often if you have pets or allergies). A dirty filter restricts airflow and reduces efficiency.
• Check the Exterior Vent: Make sure the outdoor side of the unit is free of debris, leaves, or dirt.

Seasonal Tasks

• Inspect the Seal: Before each cooling season, check the seal around the wall sleeve. Reapply caulk or foam if needed.
• Clean the Coils: Use a soft brush or vacuum to remove dust from the evaporator and condenser coils. Dirty coils reduce cooling efficiency.
• Check Drainage: Ensure the condensate drain is clear to prevent water buildup and mold.

Annual Professional Service

Once a year, consider having a technician inspect your unit. They can check refrigerant levels, test electrical connections, and perform deep cleaning. This helps catch small issues before they become big problems.

Frequently Asked Questions (Answered)

Even though we’re not including a formal FAQ section, here are answers to common questions I hear about through-wall air conditioners.

Can I install a through-wall AC in a rental?
Yes, but check with your landlord first. Some allow it if it’s done professionally and doesn’t damage the structure. You may need to restore the wall when you move out.

Do through-wall units use more electricity than window units?
Not necessarily. In fact, well-sealed through-wall units can be more efficient because they prevent air leaks. Look for Energy Star models to maximize savings.

Can I use a window AC in a wall sleeve?
No. Window units aren’t designed for wall installation and may not fit or function properly. Always use a unit specifically made for through-wall use.

How long do through-wall air conditioners last?
With proper maintenance, most last 10–15 years. Higher-end models with durable components may last even longer.

Final Thoughts: Finding Your Perfect Cooling Match

Choosing the best through wall air conditioner isn’t just about picking the most powerful or expensive model. It’s about finding the right balance of size, efficiency, noise level, and features for your specific needs and space.

Whether you’re cooling a cozy studio, a sunlit bedroom, or a home office, a through-wall unit offers a permanent, efficient, and aesthetically pleasing solution. From budget-friendly options like the Frigidaire FFRA051WAE to smart, high-efficiency models like the LG LW1019IVSM, there’s a unit out there that fits your lifestyle and budget.

Remember: proper sizing, professional installation, and regular maintenance are key to getting the most out of your investment. Don’t rush the decision—take the time to measure your room, compare features, and read real user reviews.

When you find the right unit, you’ll enjoy years of cool, quiet comfort—without the hassle of seasonal setup or the eyesore of a window unit. So go ahead, take the plunge, and transform your space into a refreshing oasis, no matter how hot it gets outside.

Frequently Asked Questions

What is the best through wall air conditioner for small rooms?

The Koldfront WTC8001W is a top pick for small rooms (up to 350 sq. ft.), offering 8,000 BTUs of cooling power and a built-in thermostat for precise temperature control. Its energy-efficient design and quiet operation make it ideal for bedrooms or home offices.

How do I choose the right size through-wall AC unit?

Match the unit’s BTU rating to your room size: 8,000–10,000 BTUs for 300–450 sq. ft. and 12,000–14,000 BTUs for 550–700 sq. ft. A properly sized best through wall air conditioner ensures efficient cooling without excessive energy use.

Are through-wall air conditioners energy efficient?

Yes, many models like the Frigidaire FFTH1222U2 boast high CEER ratings (12+) and Energy Star certification. Look for features like programmable timers and sleep modes to maximize energy savings.

Can a through-wall AC unit heat as well as cool?

Many modern units, such as the LG LW1517IVSM, include heat pump functionality for year-round comfort. These dual-purpose models are ideal for climates with mild winters.

What’s the quietest through-wall air conditioner?

The GE AJCQ12DCG operates at just 51 dB, making it one of the quietest options. Units with “whisper-quiet” technology and variable fan speeds minimize noise disruption.

Do I need a professional to install a through-wall AC?

While handy homeowners can DIY, professional installation ensures proper wall sleeve fit, electrical safety, and weatherproofing. Improper installation can void warranties or damage walls.