Can You Put A Mini Split Condenser On The Roof?
You can mount one of these mini split outdoor units just about anywhere outside your home that fits your fancy. Just use enough common sense so as to aid in servicing and maintenance. The roof can offer some obstacles when installing and repairing mini splits.
Obviously a tall house with a steep roof would scare off a few installers or service technicians. And fowl winter weather could limit accessibility. If a unit failed during a snow or ice storm you better have another source of heat.
Don’t be so afraid of a roof penetration that you end up with something as ugly as the line set in the image above.
The intense heat of summer can make your unit work harder that normal with the reflective heat off a roof. All these things are relative to the area you live in so you’ll have to adapt what I’m saying to your respective climate. Some manufacturers may say in their installation instructions not to put a mini split outdoor unit on a roof.
Installing any heating and air conditioning system on a roof can lead to leaks in the roof and a rotting structure. Just more stuff that needs periodic maintenance with caulking and roof repairs. I currently have a leak in my roof that is just driving me crazy.
Not from a mini split, but none the less it’s a leak and it’s causing some damage that I will soon have to repair.
Why Would You Put A Mini Split On A Roof?
With setbacks for houses shrinking to allow for more homes with literally no lots it’s come to a point in time when you can’t even run a wheel barrow between the home and a fence. So where are you gonna put an AC unit?
Of course who needs a wheel barrow when you have no lot.
I can see why someone would want to put an AC unit on there roof. But I think access needs to be addressed. Where are you going to put a ladder with enough angle other that almost straight up to get on the roof?
Especially as these homes get taller and narrower. Add a little fowl whether and if it’s a heat pump you may have to wait for repairs.
An alternative to a roof when you have such small setbacks is to mount the unit up about 7 feet on a wall bracket so you can walk under the thing.
Is There A Mini Split Roof Mount Bracket?
Using a manufactured roof mount bracket is a quick and easy option. I did a search for what’s available. Most people search on Amazon and I only saw one and it was hard to find. It’s adjustable for different roof pitches.
Called a Rectorseal 87745 Slope Stand and it surprisingly inexpensive, but when I looked they only had one left in stock.
DiversiTech makes a roof bracket model QPR1000. This unit looks a little sturdier than the Rectorseal bracket.
But what a price difference. I don’t know if it’s worth the price, but like I said, it does look stronger and that may be what you want with a 150 pound something up on a roof over your head.
What Other Alternatives Are There To Mounting My Mini Split On My Roof?
This is my favorite, a wall mounting bracket for ductless mini split air conditioner condensing units. There are several brackets like the one below available at Amazon. You can click here or on the image below to check them out.
A wall mounted bracket keep the unit off the ground and provides a clean looking installation that is easy to clean under and keep away from most snow fall.
The Worst Way To Mount A Mini Split Condensing Unit
In my opinion the worst way to mount a mini split outdoor unit is on a mini split mounting pad, especially a heat pump. It’s a little different with a cooling only unit because they don’t operate in the winter.
I know you wouldn’t do this. Not much pride in the work. I know the ground can shift over time, but there are precautions to take to prevent this much movement.
Or someone does some landscaping and undermines the original installation. Who knows?
What difference does that make you ask? A heat pump can get covered in snow and ice in a lot of areas of the country. It’s important for a heat pump to stay clear of the snow and if it’s mounted up off the ground a foot or two it has room to defrost and drain and breath.
Mini splits hung on an outside wall are also easier to clean around and keep free of weeds and grass.
Some of my customers were worried about vibration or noises being transferred into the home if hung on the exterior wall of there home. I’ve never had a complaint.
In fact they couldn’t even tell if the unit was running without putting a hand in front of the fan to see if it was on or not.
This next image is of a weekend DIY project. The customer called me to see if I could get it running. They had bought the system from a friend in the HVAC business in another state. They had lost the Freon charge and fried the compressor by trying to start it with the valves closed that release the Freon into the indoor unit.
It looks incomplete, but it was the finished product. Notice the electrical power wire hanging from the unit and the communication wire with no protective cover and no grommets. By the time this job was redone it involved a new outdoor unit and a complete change in looks. And, a happy customer who will think twice about DIY refrigeration work.
Lets Rap Up This Mini Split On The Roof Thing
To every thing there is a season, and a time to every purpose under the heaven
We all have to pick our battles. Every house, every job, combined with every different person involved creates a new situation that creates a unique job or opportunity.
This mini splits have a purpose and provide a sweet innovative opportunity to provide warmth and cooling in a very efficient manner.
The sky is almost the limit when it comes to how you can apply and install these mini split systems. The line sets can run up, down, or even sideways to complete a system which makes your choice of installation locations a product of your imagination (as long as you adhere to the installation instructions of course).
Many installation manuals say don’t mount on a roof. What is the downside to mounting on a roof? Is it just poor performance for cooling due to the heat up on the roof? (This is for a region with no snow and little rain.) Aesthetics and saving real estate seems to make roof mounts quite advantageous if possible even though the install will be more difficult.
Dag, I see so many of these units of roofs. Don’t know the particular reason for the install manuals to say don’t put one there. I’d call the manufacturer and ask (I may do that myself) and then depending on what they say, make a decision base on your new knowledge. Chad
Living in a co-op two story flat roof and current A/C directly over head.
Can a mini-split replace my current unit?
Living space is 700sqft
Douglas, I Googled “co-op two story” and got back mostly images of chicken coops so I’m sort of at a loss of what you live in. Taking it as just a two story of 700 sq ft does that mean 350 up and 350 down? Don’t know what your existing system is? But it sounds like you should be able to use a mini split. Maybe one head up and one head down. I’m sure there are some companies in your area that will give you free estimates. Nothing like being there to know if something will work or not. Good Luck. Chad
Chad, thanks for all of the info. It is very helpful
My question is related to the outdoor condenser unit for a mini split. How much air space is required surrounding the unit to provide sufficient air flow. I have a tight area that I’m working with
Thanks
Niles, you can always refer to the installation manual for clearances around the outdoor or even the indoor units. The clearances vary according to brand so I can’t tell off hand. -Chad
Follow up question:
I was told mounting on the roof causes issues during shutdown / unit not running with oil migrating down the lines to the air handler ?
Rodney, that’s a good question to call your brand’s customer or tech support. That way you know your warranty would be valid and you won’t have me to blame if something goes haywire. Chad
I am reviewing proposals for a roof install of 1 condenser and 4 unit heads in a 3rd floor/top condo unit. Instead of an exterior long drainage pipe from the 3rd floor from each unit head to ground floor, can you put a hole opposite the unit at the third floor level with a short tube for drainage? This was an option proposed by one company but another company said this was bad practice. I have heard that the small interior condensate pumps are noisy and unreliable. I am trying to avoid an unsightly drainage pipe in 4 places down the side of a condo building.
Cece, yes the interior pumps are noisy and troublesome. I don’t know of any issues with an exterior drain pipe.. Doesn’t mean there aren’t any. You might try a drain pipe and if it causes a problem install a pump. Good luck. Chad
Excellent article!
Does the air handler have to be installed on an exterior wall?
Joshua, You can mount the indoor unit on most any wall but it becomes more difficult to run condensation. You may have to install a condensate pump. Search my site for installing a mini split on an inside wall. – Chad
Chad,
Thanks for this blog, your articles and replies are great.
I think I can skip the roof for a 4 zone mini-split ductless job at my house, but I am limited where I can put the indoor units. What is the risk of getting the indoor air handlers too close to the ceiling? I am looking at a MR Cool DIY 12k handler and it recommends a 5.9 in. min clearance to the ceiling. It looks like I can fit it on the wall (due to windows) with a 3.5 in clearance to the ceiling and then avoid condensate a noisy pump and longer run.
What is the impact on performance of the handler being too close to the ceiling?
Christopher, It wouldn’t be advisable for warranty reasons. If (big if) you had any problems that and the location of the indoor unit were known then warranty could be denied. On the other hand, I can’t imagine that the unit mounted at the height you mentioned would create any lack of air. Sometimes life is just a crap shoot. Good Luck, Chad
My HOA won’t allow for ground installation, only on the roof. Can the lines just go threw the roof into the garage below into the air handler which would be a very short distance? Or do the lines have to run down the side of the house. I have a flat roof with a 3ft parapit and that’s a pretty long way for all the lines to go up around the parapit and down the outside wall of the house then into the garage.
Ken, Sounds to me like the best way, avoiding those parapit walls. Be sure to check into your manufacturers minimum length for refrigeration lines. – Chad
I’m about to install a DIY unit with the condenser on a flat roof on top of my garage. If I understand correctly, one still needs to have a drainage line from the air handler and that it needs to run downward in order to prevent a backup of water. So, do I run the coolant lines up to the condenser and run the drainage line down and outside somewhere at ground level?
Yes sir, you get it.
I would like to put the outside unit above the garage roof on a second story wall. This gives easy access to the attic for the two rooms upstairs and access to the two rooms and electrical panel downstairs (one wall buts up to the garage, the other wall is under the garage trusses, as is the electrical panel) Does code allow this? It has the shortest runs, easiest access and highest efficiency rating location I could find. The garage roof is easy to work on being a 4/12.
Bob, I think that would be a great place. But as you know I’m not the final word. Always check with your local building department. You’d hate to have to move the thing if somehow it didn’t meet local code. I don’t think you will have a problem. – Chad
can a minisplit A/C with heater be mounted flat …..parallel to the mounting plane?
Mark, Pardon my lack of imagination or inability to understand your question, but I’m not following your line of thought. I’m assuming indoor unit since it has a mounting plate. And A/C with a heater, do you mean a heat pump? Really lost on the parallel to the mounting plate part. Sorry! – Chad