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In-wall AC units are a needle in a haystack for most New Yorkers looking to rent, especially in older, historically built homes.
Usually, we end up lugging our heavy in-window units from one apartment to the next, sacrificing daylight just to sleep through the night without star-fishing or drenching our sheets.
For renters, finding the right AC unit can feel like a project in itself. First, you’ll need to figure out your BTU requirements to see how much cooling power your space needs. Then comes getting your landlord’s okay before making any wall cuts — and deciding which bells and whistles you want, whether that’s smart controls, energy-saving settings, or winter-proof features. If you’re nodding along, we’ve got you covered.
The Friedrich WallMaster offers unrivaled commercial-grade construction in a sleeker package suitable for a variety of spaces. Having lived with this exact older model for nine years, there was no question that our 15-year-old Friedrich would be replaced by Friedrich itself, since no other brand comes close.
While the price tag might be a shock at first, it’s important to remember that this unit is built to last. Truthfully, when divided by year, it’s only $93 or so per year (over 15 years). And given the strength and reliability of this machine, I’d argue it’s well worth the cost.
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Pros:
I had already been using the older version of this unit for 9 years, and it has held up very well over time
The WallMaster is a newer model, which has some smart features like wifi and in-app controls
An inverter compressor that saves money on your electric bill and usage
Cools my entire railroad-style apartment, including the bedroom on the opposite end of my apartment
Cons:
Need someone to install it for me since the unboxing and actual unit are quite heavy
The newer remote doesn’t show the temperature
The Wi-Fi-powered WallMaster is equipped with advanced sustainability features to provide optimal comfort while also helping cut energy costs. A variable speed compressor adjusts the power based on needs, so your space stays at just the right temperature and you don’t waste extra power. It’s also engineered with QuietMaster technology, so you shouldn’t be up all night hearing it rattle around.
The WallMaster comes in four different BTUs, and you can nail down exactly what size is best with Friedrich’s air conditioner guide. Typically, the BTU is based on the size of your space. The higher the BTU, the more powerful the unit — and the faster it can cool your space. If you pick one that’s too small, your room will never feel truly comfortable, and you’ll waste energy while cycling on and off constantly.
This unit is not like the duct-taped model you found on Facebook marketplace; it’s designed to last with commercial-grade materials that are designed to perform in extreme conditions (blazing summers included). For peace of mind, all Friedrich WallMaster units come with a two-year parts warranty.
Cooling: 10,000–16,000 BTU | Heating: 10,000 BTU | Compressor Type: Inverter-driven/variable speed | Special features: ENERGY STAR certified, Smart Control, Precision Inverter, QuietMaster Technology, Sustainable Design
Our Review
After nine years in our apartment, we began to notice some severe leaks in the kitchen during the hottest summer on record. According to our landlord, our in-wall unit is estimated to be about 15 years old. That’s right on par for the time for a replacement. Older units tend to be less efficient and more prone to breakdowns, per guidance from Energy Star.
We stopped using ours out of fear of damaging the walls — which was brutal — until the new unit arrived and could be installed. That’s when we realized the previous installation hadn’t been done professionally; the ancient unit was actually still in perfect shape. Even though we experienced the leak, which turned out to be unrelated, we had zero doubt that the replacement should be a Friedrich.
Walking around Greenpoint, Brooklyn, you can see that nearly every apartment in these classic railroad layouts uses Friedrich units. It was an obvious no-brainer for me and my family. The WallMaster is well-trusted in a city that sweats all summer long.
Unboxing
Michelle Moezam / Post Wanted
Full disclosure: the unboxing is tough if you’re short and not especially strong, like me. The unit itself weighs over 100 pounds, far too heavy for me to handle alone. That said, the packaging, shipping, and delivery were actually the most seamless I’ve ever experienced for a large unit like this.
Friedrich connects users with local installation services (as well as repair services, if those needs arise). I got a text 30 minutes before delivery, and the driver brought it right into our first-floor apartment, placing it carefully in the kitchen. Luckily, there were no stars to navigate, which seriously expedited the process.
The wrapping was secure, and the custom cardboard box kept the unit from rattling around, so it stayed intact with minimal impact. This also made it much easier to place the older unit (pictured) back into the same box to move into the basement.
Installation
Michelle Moezam / Post Wanted
The only reason I needed to replace my old AC was that we didn’t know its exact age when we moved in, and some parts started acting up. After a closer look, we realized the unit itself was still working; the issue was the installation. This time around, I wanted to make sure we got things right.
Luckily, I didn’t take any chances and let Friedrich’s trusted installer handle the job instead. John is the owner of Advance AC & TV, and his expertise was made apparent — he was faster, safer, and looked far less stressed out while getting the job done. He also answered all of my questions and gave me his contact information if I needed any help down the line.
John even worked with my landlord to store the older unit in the building’s basement, which meant carrying the heavy unit down a flight of stairs. This wasn’t in our original agreement, but he did it anyway, all with a huge smile on his face. The customer service was top-notch.
Performance
Energy efficiency: This unit has been surprisingly easy on my electricity bill. The energy-saving mode and sensitive temperature gauge allow the machine to turn on and off automatically, while Friedrich’s Precision Inverter variable speed compressor adjusts up or down based on need. Compared to traditional on/off units, Friedrich’s Soft-Start technology starts the compressor with significantly less strain to save energy.
Noise and vibration: Even on high power, the WallMaster is remarkably quiet. It’s not completely silent, but I don’t hear any rattling or vibrations through the wall. Considering how much air it’s moving, I find this very impressive compared to other machines I’ve had to listen to.
Winter-proof: I tested the older unit over the past nine years and never once felt cold air coming through. The perfect Friedrich-specific installation and sealing method made this possible. These models are definitely tough enough to survive an East Coast winter 15 times in a row.
Our Review after 1+ Months of Use
My husband is obsessed with the in-app and smart features this newer model offers. The updated remote doesn’t display the temperature like the older one, so setting everything up in the app is much easier, and we don’t have to worry about losing the remote. The energy-saving feature has been a huge plus with this newer model. The temperature gauge is more sensitive, so it knows exactly when to turn on and off, helping keep the room comfortable without wasting power.
Our kitchen feels much cooler now, and we never have to sacrifice our only source of sunlight or overheat the space when we use the oven for long roasting sessions. The fresh air circulates fast, and even on hot days, I can breathe without gasping for fresh air. This newer model is also impressively low on noise, which means zero disturbances. Pure relaxation — the way it should be.
How it Compares to Other In-Wall AC Units on the Market
There are a few other brands that offer in-wall AC Units. But the WallMaster is the only replacement AC for existing 27″ sleeve units. Frigidaire and GE Appliances offer some other popular units that I’ve heard of, but they don’t offer another AC Unit fit for these sleeves.
While it’s true that other in-wall AC Units are also reliable and cost-effective, they tend to be noisier compared to Friedrich’s offerings, in my experience.
I used to live with a Windmill window-unit, and the noise levels were off the charts. I also didn’t find that it was cooling consistently over time. The Friedrich WallMaster series is equipped with QuietMaster technology, which ensures whisper-quiet operation that customers like myself can seriously appreciate.
How it Compares to Older Models
We had been using the older model for nine years before testing the newer model for over a month now. Compared to the previous WallMaster model (without the smart features), the newer unit feels quieter, easier to use, cleaner, and now properly installed.
The Bottom Line
While this unit is definitely a splurge, I cannot recommend it enough. It’s been a part of my life for nearly a decade, and I honestly couldn’t imagine living without it. I’m thrilled and relieved to know it’ll last another 10 years, and now that it’s been expertly installed, I have zero doubts about its longevity.
How We Tested
While testing Friedrich’s WallMaster Inverter Smart AC, I considered the ease of installation and overall customer service, as well as the cooling performance, filter and care instructions, and smart features.
Michelle Moezam / Post Wanted
Customer Service and installation: The highlight of my experience was the quality of customer service and seamless installation, set up through Friedrich. My service expert, John Plaut with Advanced AC & TV, answered all of my questions and worked fast. The entire process took less than 30 minutes, including the removal of my old unit.
Cooling performance: This unit can get my 900 sq. ft. apartment cool in about 15 minutes. It works very fast; I can take my dog for a walk and come back to a comfortably chilled apartment instead of sweating bullets. The blast of air also circulates well, so I don’t have to crunch over a corner to enjoy the air conditioning.
Filter and care requirements: Cleaning the filter is quite simple; I just climb my little step ladder and pop the cover off, remove the filter and wash, dry, and then snap it back in place. Sometimes I’ll even just vacuum the filter if I am feeling lazy, and while that’s not technically recommended, it seems to do the job just as well.
Smart features: Having the ability to use the app is a huge game-changer. We can also set it to turn on before we get home, which helped on those horribly hot days we all faced this summer. Best of all, the temperature gauge knows when to turn off and conserve power on its own, making my job simpler and helping save energy.
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