More Q&A Spotlight
Ductless minisplits have become the standard for heating and cooling in many high-performance houses. These air-source heat pumps have many advantages over more conventional HVAC equipment, and also what some homeowners consider a glaring flaw: the indoor fan units that are typically hung on an interior wall are not especially attractive.
Such is the case with CarsonB, who recently posted his plans for concealing a ductless minisplit head in the Q&A forum.
“Here’s my idea to hide a minisplit head,” he writes. “Please critique and tell me why this won’t work. Keep in mind that the ducted install was a lot more expensive and the floor units are large and just don’t look good IMHO.”
CarsonB outlines his approach with these three steps:
- Mount the Mitsubishi head just 18 inches off the floor, a tip that CarsonB found at BuildingGreen in an article posted in 2013.
- Inset the head into the wall as far as possible.
- Build what he calls a “console table” one with no face or back to block the flow of air, over the head to keep it out of sight.
An HVAC contractor is concerned about air from the head bouncing off the floor and interfering with the system, but CarsonB still finds the idea attractive.
“Sounds ideal for hiding it,” he says. “I don’t think anyone would ever notice it.” Or, is the idea crazy? That’s the topic for this Q&A Spotlight.
Don’t mess up the flow of air
Yupster cautions CarsonB not to disrupt the flow of air that engineers envisioned when they designed the head. “These are carefully calibrated units,” Yupster writes. “Mess up the airflow, you mess up the unit. You also need access for maintenance, both for the inevitable mechanical breakdown and the…
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52 Comments
We use them always in Latin America, and you get used to the appliance as you get used to seeing return air grills, dishwashers, and other household artifacts. Living in Guayaquil, where it's always 85-F or more, and always 100% humidity, we used the mini-split only in the bedroom on still nights without a breeze. It works very well, and there's no need to cool the whole house. Now we live in Houston and live year-round without AC, ceiling fans only. If you limit airconditioning, you don't need such complicated sealing techniques and costly HVAC systems. Simple, point cool and let your body adopt to the climate.
I'm pretty sure if I let my body adapt to my climate, I would die of exposure. ;) #canada
you are a lot tougher than most Americans. I lived a few years in Austin after moving there from colder climates and couldn't imagine living there without AC. Heating is a definite must for survival where I am now though.
I could only sorta adapt in Panama because very few places were air conditioned. I could never adapt in Houston with the heavy use of AC in buildings.
Wow, I never expected this to reach the spotlight. I will try to post results when our house is finished.
I really appreciate the suggestion for the kit to set the floor unit behind the wall - that seems to solve the issue I had with not being able to mount the Mitsubishi ducted unit vertically and seems a lot more DIY friendly than trying to setup the Fujitsu unit upside down with a custom duct. I was unable to find any such installation in searches.
minor correction: "(Indoor units, Dorsett points out, can be ordered in black.)" Indoor "wall" units can be ordered in black. The mitsubishi floor units are only available in white. I'm not sure how easy it would be to paint the units, I'm assuming you would want to remove the plastic casing before painting which hopefully would not void the warranty.
My decision making process. I had one of two walls in the main area of the house. The first is the view as you walk in the front door, so you would be staring at it as you walk in
The second is obviously where it ended up. You only see it head on or from a small section of the dining room.
No one mentions it
As you can tell, there is no way to mount one on most exterior walls.
[edit] you can tell I am bored with social distancing, I bothered to take pictures, resize them and figure out how to attach them]
That's some WEIRD looking tropic fish you have in the tank under the mini-split, with some unique aquarium lighting too! How do you get that neutral-density turquoise to work? :-)
My daughter watching Johnny Test on a break from her online studies
Keith,
Great example of a mini-split hiding in plain sight.
Yeah, when you place it so it is not the focus when you walk in the room, it really does not stand out. That and minimizing the side profile[they are so much thicker than they look in pictures]
today i would totally go with the ducted units, if you look at the top right corner of the pic taken from the stairs, you can see a detent in the wall, and the beginning of a ceiling for the little short hallway. That is where the entirety of the 'attic' in the house is, and would easily hold a 2 ton ducted unit. In almost the same place on the lower floor, a 1 ton unit would handle the bedroom and family room, and a 3rd for the other bedroom would mean that I could have heated/cooled with essentially the same number of units. But ducted units were much more expensive and less efficient 10 years ago.
Keith, house is looking good! I am a big mid-century modern fan.
It's hard to believe that this lovely residential style of the 60's co-existed with the more urban Brutalist movement.
Hard to believe this house was built with single pane glass!
I would hate to see an entire city of Brutalist buildings, would see so very soviet, but people are starting to see the 'charm' if you will.
I could easily live with and celebrate a minisplit head. My wife, no way in heck. I mentioned it to her and she immediately wanted nothing to do with it and insisted our place have conventional ductwork. So much for that idea.
Same. That’s why I’m going with unconventional conventional ductwork :)
How about using ceiling-mount?https://www.mitsubishicomfort.com/products/indoor-units/recessed-ceiling-cassettes-and-ceiling-suspended/gallery
Anything more than a standard wall mount unit seems to double the price while reducing performance, making them financially unsuitable, in my opinion.
The pricing is not as bad as it once was
They are still not state of the art WRT performance, but as with all things, the incremental improvement as the numbers go up is smaller
The material cost of the ceiling cassetts aren’t that bad. Installation may be another matter, probably dependent on how many your contractor has installed. Unfortunately for my application the cassetts weren’t an option as there’s no ceiling cavity to put them in.
My wife is from Central America where ductless mini split air conditioners are common place. She actually thinks grills and ductwork are weird!
We went for a modern look with our house. Everything is white so you barely notice our Fujitsu unit. This one unit heats and cools our entire house for very little money. What's not to love?
Rick,
Your photo sure provides another convincing argument for leaving them exposed.
Attitudes likely will shift in the US eventually, especially when people actually look up how much they are paying for all that ductwork in both labor and efficiency. Still, shiny white plastic boxes don’t fit in every home. Fortunately mitsubishi at least recently introduced a matte black option for their wall units. LG is far and away the leader in stylish head units, unfortunately no one in my area installs them :/
What's the likelihood of the lineset having a leak in it at some point in the future and needing to be replaced? I built a house in 2017 and besides my wife not liking the the head unit, I didn't want to deal with running linesets in the walls, only to rip apart the wall in the future to get at the lineset.
Having worked with refrigerants as a mechanic, at some point, the current refrigerants are going to be replaced with something more friendly to the environment. With the changing of refrigerants, HVAC techs prefer to switch out the linesets to ensure a proper install instead of dealing with cleaning out the current lineset.
With those ideas in mind, burying any of the head units is only creating more hassle in the future unless the homeowner ensures there is access built in. Neither of the HVAC contractors I talked with thought of future proofing the installation.
Just a thought.
The 2004 AC unit on the side of my townhouse still has the factory fill of R22 (I think) and, touch wood, still works as intended. 16 years and counting, and I don’t see why you wouldn’t expect a similar life from a decent mini split?
Yes R22 is phased out, but if this thing gave up tomorrow it wouldn’t owe us anything.
Most linesets are put straight through the wall behind the wall unit, so as long as the new wall unit covered up (or used the same?) hole you’d have no worries about drywall repair.
i think a line leak is very unlikely
Of course care in hanging shelves and pictures helps
you can see from my pics the issue in my house, there is no unwindowed space on the long walls of the house, at all.
The line sizes appear to have remained unchanged for a given size for quite some time. I installed my first 15 years ago, and it would be a drop in to change it today
I think most repair guys are assuming the lines are over 40 years old, and maybe then the lines should be replaced. If we get to that point, we might be changing more than just an AC unit. I hope to get 20 years out of my units, and by that time they will seem really inefficient.
We're doing a black one on a dark 'feature wall" that will also have a large tv and a sound bar on it, this will cool the main open concept living/kitchen areas, and a similar one in the master bedroom disguised similarly. the guest area (2 bedrooms and a jackand jill bathroom) will only have fans as they will be unoccupied 90% of the time. I'm hoping the north facing office area will be ok without one but we could add another specific to this area later if we have to.
I'll soon be installing one, and with airflow & maintenance in mind, I'm going to recess it into a floor to 'ceiling' bookshelf, after veneering it with stained wood
emdog, please post a picture when done. There are a few, but not many examples online.
A couple of decades ago it was refrigerators that were suddenly seen as unsightly. You could buy kits to cover the doors to match the cabinetry. I remember FHB Magazine had an article on how to do it. Then, just as suddenly, no one cared.
I have a design-build firm in Northern New Jersey and we have been using mini-splits for several years now with great success. I do however agree that the wall units are not particularly attractive. Our projects over the past few years have used ducted mini-splits. When designed and used for a new master suite, small apartment, or similar combination of rooms, the cost is very competitive. A 12K Fujitsu slim-duct has handled the heating & cooling needs of several 600 SF spaces very well, including below zero winter conditions. In New Jersey, the utility company currents offers a $2,000.00 rebate for ducted mini-splits, which makes them extremely affordable.
We are in design for a new lake house, using four ducted mini-splits for a 3,200 SF house. The house will be also have a PV solar system with battery back-up.
My belief is that natural gas boilers & furnaces will quickly become the pot belly stove's of yesteryear.
Peter, I agree that minisplits will quickly take over the market, and seem to already be in many places. Did you get installation quotes for the ducted vs ductless units? What were they like? I ran into the issue of many quotes for both seemed to be in the same ballpark as having the entire house ducted, and it was rare to find one that seemed to acknowledge that a ductless unit is a much easier install.
Hi Carson. We've had installed both ducted & non-ducted (wall mount) mini-splits. The single wall mount is less expensive, about half the cost of a ducted system. However, a single wall mount can heat & cool only one room. The velocity of the airflow is also much higher than the ducted, which can create uncomfortable cool air blowing on an occupant. The inherent design of the supply air blowing from the bottom of the unit and the return above makes for a very simplistic air movement in the space, which may not be very accomodating. The wall unit can also be a little loud, where the ducted unit is stealth quiet at even maximum fan speed.
The economy of the ducted unit is that a single system can handle multiple rooms. Our office is 600 Sf, consisting of three separate rooms, and bathroom, and plotter room.
The comfort level is excellent. We have used ducted mini-split systems for offices, master bedroom suites, basically up to 3-4 room areas.
As an added benefit, the condensation line is piped to a 3'x8' outdoor landscaper area that keeps the garden well watered (the hotter it is, the more condensation water).
Lastly, in this time period of the pandemic, the ducted mini-split filters can be changed to have a high MERV rating to help minimize air pollutants. A wall mounted unit does not have an options with regard to the filter strength.
Post lastly, in regard to appearance, there is not the slightest possiblity that if all things were equal (and there not) that a client would rather have a 3'0x 1'0 appliance hanging on the wall instead of a concealed unit. We used a ducted mini-split in an historic farmhouse alteration. The supply and return duct covers utilized cast iron grates, which blended perfectly with the existing residence.
that is an excellent rundown of the benefits of a ducted system. For me the cost was the primary issue, and your number of double is about right. However instead of installing heads in every room, I have 2 indoor units in a great room, with the bottom unit hidden with the kit listed in this article. My plan to distribute that heat is to use the ERV exhausts for the bedrooms, pulling warm air into the bedrooms to help equalize temperatures. I guess I will just have to see how well that actually works.
Carson,
That's an interesting approach. Typically bedrooms are supplied with outside air because they are the one area of a house that gets closed off for extended periods of time with the occupants present and experience high co2 levels.
The numbers don't generally support trying to equalize room temperatures through ventilation, as the amount of air necessary to warm the room is well above that supplied by the ERV, given the low temperature of the air being introduced.
Malcolm,
I'm honestly not sure how to make that calculation, is there an article you are referencing? In my mind it's circulating air either way - either pulling in 20CFM of fresh air from the outside or exhausting 20CFM of bedroom air and pulling in "fresher" air from the main house. The difference is that the outside air would be ~13% of 32F-72F delta below indoor temps, while drawing in air from the house would be above the bedroom temperature. Already that seems like a fairly large win in terms of maintaining the bedroom temperature.
As far as enough CFM to warm the room up I don't know, but even at a ~6F temperature difference, 20CFM of continuous ventilation seems like it would make some difference in minimizing the delta between the main house and the closed bedroom. If I use the formula Ac/h = (CFM * 60) / (volume in feet), then the number of air changes per hour for a 1000 cubic foot bedroom would be (20*60)/1000 = 1.2 air changes per hour. In an efficient home with U.26 windows and R28 (effective) walls I would think that there would be very little temperature drop in less than an hour.
I don't find wall mounted heat pump units at all unattractive, but I realize that is a personal aesthetic choice and I'm not likely to convince others who disagree.
If the ceiling joists are deep enough, you might consider a recessed ceiling cassette indoor unit. once installed, it more or less looks like the grill of a ducted unit, but (depending on line set and condensate drain access), they can be closer in price to a wall mounted unit than a ducted system.
Mitsubishi, in particular, has started to offer some high performing and pretty attractive options:
https://www.mitsubishicomfort.com/products/indoor-units/recessed-ceiling-cassettes-and-ceiling-suspended
I have been saying for years that the market is just waiting for the minisplit companies to hire a name brand industrial designer and design a super cool looking head unit - it is bizarre to me it hasn't happened yet. The first company to do it will own half the market. Unfortunately the Japanese companies are not so good at this (Koreans seem better).
Count my wife as another "absolutely not". A cool 21st century appliance with a brushed aluminum box, proper design, etc.? It would be a yes.
Brad, I completely agree. LG with its art cool line seems to be leading the pack. Bizarrely, it wasn't even until recently that you could get them in black. Shiny white appliances have been out of fashion for several decades.
> consider a recessed ceiling cassette indoor unit
Given the air sealing implications of the ceiling, I'd like to see an "upper interior wall recessed unit".
I would like to see a unit designed to fit in the back of a cabinet with a register at the toe kick. Feeling the heat on your toes while doing the dishes is one of life's great pleasures.
To help anyone else looking at floor unit kit mentioned in the article, the link in the article is now broken and the model number is incorrect. The actual model number is MAC-760FD-E. Posting a link again will likely just break in the future, but googling that model number should pull it up on mitsubishi's "mylinkdrive" site.
I was concerned with the appearances before I had them installed but my contractor really resisted the idea of anything like a branch box or ducted units so I ended up going with the wall units and like most people say and you end up not really noticing them after a while. Besides I have one wall unit for my main living area and if I went with central air I would have, I assume, at least three or four ceiling vents in that area and a return to look at. The only thing I wish I did is get the Mitsubishi designer units for the bedrooms. mine are all white and obviously with lighter color walls they blend in more but in my opinion they don't look bad anyway.. The first picture is in our living room the second one is in a bedroom.
you could probably paint it? It does match the trim however, so I don't think it looks out of place as is.
No I'm fine with it now. I had a picture of one another room with a lighter gray wall that blended in better but I didn't Post it. It didn't take me long to adjust to the looks of them. Now the issues with humidity control in the bedrooms during the summer is a different subject.....
To CarsonB,
Thanks for updating the reference for the Mitsubishi part. I've removed the hyperlink and corrected the text with the part number you provided.
Scott
I've not seen any women post on this site but I came across this site when searching for a way to hide a mini split. I am going to be the first to chime in because I do think there is a gender difference here. Not only on this thread but on others I have come across, husbands are commenting that their wives absolutely refuse to have one of these in their homes because they hate how they look. Count me into the group. I NEVER wanted one of these ugly things in my home but I reluctantly agreed.
We have a 60's ranch with no duct work. We live in the northeast and my husband wanted something to replace a window air conditioning unit that we used to cool the living room/kitchen/dining room. Typically he would install it in June and take it out in Sept. For several reasons (one being that people said you wouldn't notice it after a while) I agreed to having one installed. I will say that it works great. I love it for that reason. However, it's been 2 years now and I still hate how it looks. If money was not a factor, I would rip it out in a heartbeat and put in ceiling mounts or ducted splits. It's on a focal wall which I was told was the best place for it and so my eye goes right to it.
I spent nearly 20 years remodeling our home and I tend to favor a more traditional style----wainscoting, crown molding. This doesn't fit in at all and I think it detracts from the room. My husband thinks it's fine. My adult son thinks it's fine. My adult daughter thinks it's a monster that doesn't do anything for the room. My female friends say they wouldn't like it in their house either. My mom think it looks like a big appliance hanging on the wall. My dad says it's fine. My sister's mother in law is looking for ways to hide the one that her husband had installed in their house. So I definitely see a pattern here.
I agree with Brad L. If someone comes up with a way to make these look better (and smaller) they would own half the market. I even talked with a representative at Fijitsu and asked if they were working on any new models that would be smaller or look better. He told me they were not and not likely to and he also did not recommend I paint it because of the warranty. I have looked off and on for 2 years now for ways to hide this thing or make it less noticeable but I have not been able to find anyway except to totally renovate the room. Most of what I see can not be done in my house.
Although I didn't love the window air conditioner, at least I knew I only had to look at it for maybe 4 months out of the year. It spent the other 8 months in the garage on a shelf. (we only use the mini split for cooling but I get to look at all year long). So I am putting it out there that it is not true for everyone that you won't notice it in time. That has not been my experience. For me, it was a big mistake. Should have paid the extra expense at the time and hired a contractor to re-frame the joists in the attic to accommodate the ceiling mounts.
Traditional Girl,
That you only use it for a few months should make a solution a lot easier. Why not commission a nice wood feature to cover it? That usually difficult because of the practical limitations of not impeding air-movement, but that wouldn't apply in your case.
>"So I am putting it out there that it is not true for everyone that you won't notice it in time. That has not been my experience. For me, it was a big mistake. "
And 5% of people are NEVER comfortable.
We're a funny species- there are no "one size fits all" solutions to anything. For instance, I'm really partial to paragraph breaks to make long forum posts more readable, yet some seem to be happy without them. :-)
>"Should have paid the extra expense at the time and hired a contractor to re-frame the joists in the attic to accommodate the ceiling mounts."
If/when the aggravation gets high enough, Mitsubishi now has uni-directional ceiling mounts (not the oversized squares) designed to fit comfortably into 16" o.c. joist framing, no framing modifications required, much easier to accomodate than the oversized square 3-way ceiling cassettes. See the installation instructions.
https://www.ecomfort.com/manuals/7aa2016c18f664218683d2b71d68af6a.pdf
http://www.nonul.mylinkdrive.com/M-Series/R410A+Systems/One-Way+Ceiling+Cassette/
While originally only used in their MXZ multi-zone compressors, but they now sell them married to SUZ-KAxx single zone compressors previously used with their single zone ducted cassettes:
http://www.nonul.mylinkdrive.com/files/M_MLZ-KP09NA_SUZ-KA09NA2_SUBMITTAL-en.pdf
http://www.nonul.mylinkdrive.com/files/M_MLZ-KP12NA_SUZ-KA12NA2_SUBMITTAL-en.pdf
http://www.nonul.mylinkdrive.com/files/M_MLZ-KP18NA_SUZ-KA18NA2_SUBMITTAL-en.pdf
That's a really good solution, Dana. Count me in as a man that thoroughly agrees on the aesthetics with traditionalgirl. I agree that wall mini splits are pretty ugly. Has anyone ever been in a motel that has one and left saying "Wow, I really like the look of that big hulking rectangle hanging off the wall. I gotta get me one of those."
If the ceiling mounts with normal framing had been in existence when I was remodeling my home I probably would have gone with that instead of the propane fireplace I went with. And it would have definitely been a boon to the planet had I gone with that. At least I'm saving money in summer by using a whole house fan and not contributing to global warming that way. Still...
Thanks Dana. Good information--even about the paragraphs. :) . Sooo much better. I usually am just a bullet point kind of writer.
Dana,
Only your first link works for me.
Are the other links still valid/for available models?
I have one of the old 1970s Heatilator prefab fireplaces built in an outside wall. It’s functional but the idea of adding more smoke to Southern California air isn’t very attractive anymore. I’d love to convert it to a mini split hidden by an HD screen (which could run a ‘fire’ video when desired, or any other ambience). Any suggestions?
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