How Long of a Line Set Can I Get For A Mini Split? - Ask the Expert Episode 118

If you have a multi-zone mini split and you need a line set longer than 25 ft, what do you do? Find out in this video from Dan Danowksi. Video Script: Today's question is from Clower Jay from Yahoo.com: Hey Dan! I see that a line set is usually 15 or 25 feet long. I need more than that for my multi-zone ductless unit. What should I do?

If you're installing a ductless unit you're probably not going to need to have the condenser and the air handler more than 25 feet apart. If you do, we actually sell a 50-foot line set when you're choosing your line set on the website. If you need more than 50 feet, you will have to do some modifications in the field. 50 feet is a lot. That's like four Big Foots. Or maybe five. I don't know how tall a Big Foot is.

Have more questions? Just ask them in the comments below or on Facebook or on Twitter. 
Comments
Leave your comment
Your email address will not be published
Brian Gix
Loading...
I am trying to design a 6+6+9 3 zone system, and I notice that the 3 heads are in basically a straight line: 6000 BTU C HHHHHH C ---------------------+-------------------------------+ C HHHHHH HHHHHH 9000 BTU 6000 BTU Is it possible to run *one* line pair of coolant lines to all three heads, and Tee off of that one line, (but not the control) and/or Condensate?
Kyle
Loading...
No, I do not think that is possible.
Michael Simonetti
Loading...
Replacing my air handler but new one sets lower for Lin connect ! Can I braze 2 feet to lines.
Rebekah Muller
Loading...
An HVAC professional should be able to do that.
Nick
Loading...
I bought a multi zone with 3 airflow units. The lineset lengths for each room will be roughly ~20 feet, ~26 feet, and ~36 feet. How can I tell if I need to get additional refrigerant?
Dan Danowski
Loading...
The installation manual should tell you how many length of lineset a condenser is charged to handle. Additional refrigerant would be needed if those lengths were exceeded.
Poul Wewterlund
Loading...
The indoor (garage) lineset will be elevated about a foot relative to the head unit, then run horizontally for 30 feet before dropping to ground level. Is that OK? I'm planning on a 18k MRCool for my 600 Sq foot garage.
Dan Danowski
Loading...
That's fine.
Peter
Loading...
Hi, If I run the linesets thru the attic space to the head units in 3 bedroom, will I need a condensation pump to handle the vertical climb from the bedrooms to the attic? Are the condensation pumps located at the air handlers?
Dan Danowski
Loading...
You would likely need a condensate pump. Typically, the pump is installed on the air handler.
Jane Morrison
Loading...
Hi Dan, my question is, when you look at the varied costs of purchasing a new mini-split, they are broken down by BTU, SEER and indoor units being 6 + 6 or 6 + 9 all the way up to 12 + 12; what do those values represent? Thanks, Jane
Dan Danowski
Loading...
That refers to the BTU output, basically the capacity, of the air handlers. For example, a 6k air handler will produce 6000 BTUs worth of air conditioning, 9k is 9000, and so on.
Galen Steinweg
Loading...
Hi Kyle! I am installing a Mr Cool DIY multi zone 27k BTU, with 9k + 18k air handlers. The 9k handler will go in an upstairs / attic space and will require a 40-50 foot connection to the condenser. I see that I have the option to purchase different 'line set' lengths (I'm planning on getting a 16 foot and a 50 foot) however I cannot figure out if the "line set" includes electrical wires? I see some videos online showing electrical wires connecting directly from the back of the Mr Cool DIY Hair Handler unit but cannot find reference to how long these wires are, or if you can get them longer / length to match line set length? Thank you!
Dan Danowski
Loading...
The MrCool line sets should come with the communicating wire.
Heather
Loading...
We have an attic we are considering finishing into a hang out room. It's currently very old and leaky, but we'll be adding spray foam.The floor dimensions are roughly 20'x25', however the ceiling/walls are one and the same. Think triangle maxing at about 8 ft for the peak. Would the reduced cubic measurement allow me to get away with a 9000 btu?
Dan Danowski
Loading...
A 9k unit might work in that space, but it's hard to say for sure without knowing more. The only way to really know the needed capacity is having an engineer conduct a load calculation. In any case, a 12k mini-split would likely be a safer bet.
David Reno
Loading...
I have an LG duel system with 2 inside inverters and one condenser outside. One inverter with a 25-ft line set hardly heats as much as the other inverter with a 10-ft. line. Is the refrigerant separate for each line set per inverter ? Wondering if refrigerant is low for one if they are separate.
Dan Danowski
Loading...
It sounds like the system is low on refrigerant. The shorter line is an easier path so the refrigerant flows that way first. The refrigerant charge is for the system not just each individual air handler.
Jorge
Loading...
When installing a mini split, should it require the normal roll of 25 ft of refrigerant line rolled up or can it be cut shorter?
Kyle
Loading...
A standard mini-split will typically not require a 25' line. The DIY's pre-charged lines cannot be cut, and they come in 16' and 25' increments.
Greg D
Loading...
I have a soleus air mini split single zone. This is a heat/ac unit. I have 2 questions. 1 is the indoor fan on these supposed to run all the time. 2. When in cool mode are both copper lines supposed to be cold to the touch, and if not what could be the problem? Keep in mind this is a used unit that was just recently installed by homeowner.
Steven
Loading...
Mini split air handlers do typically have the fan continuously run. In cooling mode, the liquid line should be warm to the touch and the suction line should be cold. If both lines are cold you may have a refrigerant leak. Best to have an HVAC technician come and take a look at it.
mike
Loading...
if I have to use a 50ft line, should I get adapters to increase the diameter of the line so that flow resistance is less? thank you
Kyle
Loading...
That would typically not be required.
Bogie
Loading...
Hey Kyle I love your interesting remarks on this subject. I’m adding a unit in my garage and can’t add the air handler right outside because it’s right by my neighbors door entrance. Just about ten feet to his front door. Maybe twelve feet. Anyway I’d like to add it 15 paces down the house and around to poured slab with plenty of room. Add four feet from existing AC house unit. Just a little of fifty feet. Read that from previous question you had., also need to get nine btu or twelve btu. Said something about getting precharges unit on your post or someone else.,
Kyle
Loading...
For a conventional mini-split, a 50' run is no big deal. Any good technician can get the line length you need. Shouldn't be an issue. Whether or not you need a 9k or a 12k will depend on square footage, climate, insulation, etc. If you're going the MrCool DIY route (which a lot of people are), the standard lines are 16' or 25'. Obviously, you would want more than 25 in this situation. Fortunately, they just came out with coupler kits you can use to connect two line sets together. In this case you would want to connect two 25' lines. You can check out a coupler kit <a href="https://iwae.com/shop/mrcool-diy-line-set-coupler-kit-for-9k-12k-18k-line-set-ha21479.html" rel="noopener" target="_blank">here</a>. When it comes to the DIY, the smallest size available is 12k.
Tom Jones
Loading...
Been reading all your comments. I want to install a mini-split in my garage. New 2" insulated garage door, R-38 blow-in insulation in the attic. Garage is one block wall and two insulated walls between interior walls. 19X19 garage. I have to put the condenser on the back end of my condo. I estimate about 55 to 60 foot run for the lines. Your thought on the size unit and can I run the lines that long? Thanks for the help. Tom
Kyle
Loading...
Running lines that long should not be an issue for most mini-splits. For a conventional installation, refrigerant may need to be added to compensate for the additional length. In terms of size, most likely a 9k unit would do the job, but if you're in a very hot climate, a 12k is also an option to consider.
Paul
Loading...
Do you recommend flaired joints or brazing?
Kyle
Loading...
It depends on the unit. Most central split systems require brazed connections using a minimum of 5% silver alloy. Most all mini-splits use flared connections that really cannot be brazed. I have heard of techs that have brazed mini-split connections, but it is not recommended even though brazed connections are generally more leak-free than flare connections.
Gary Gilmore
Loading...
Hey Dan, So, we had a Carrier multi-zone mini split system (5 of them) installed in October 2019. The issue is with cooling, but we had some problems with heating during the winter too. We have been running our AC for about 1 month, and one unit inside is not cooling, except when another unit in an adjacent room is on. Also, the largest unit in a large room doesn't cool as well when it's very hot outside, or other units are on. A service tech came out and identified that 6 of the lines at the valves, on the outside unit (condenser ?), indicated leakage. He believed the outside unit should be replaced, but it was up to Carrier. The office contact person says they contacted Carrier (been 5 days) to see if the entire outside unit can be replaced (it's still under warranty), or if they should just refill with refrigerant, and reseal the valves (scheduled for this Monday, 6/15/20). Also, I have heard that if the outside unit is no longer manufactured, and the outside unit needs replaced, then each unit in the house would also need to be replaced. I have also heard that this self contained systems were not meant to have to be refilled with refrigerant. So, I'm a little suspicious of what is going on. What do you think? Hope this makes sense. Thank you in advance. Gary
Kyle
Loading...
Hi, Gary, thanks for reaching out. We agree with your tech. Six leaking valves is definitely an issue. Hopefully, Carrier will provide you a new condenser, since it sounds like that one is having issues. As to your questions, if your condenser needs to be replaced, do your air handlers? It depends. If you replace the condenser with a completely different make and model, then most likely the air handlers would have to be replaced. However, if you replace the condenser with a similar make and model, that should not require replacing the air handlers. Also, ductless mini-split systems can be charged and refilled with refrigerant as well as any air conditioner or heat pump split system. Any tech should be able to do that.
Jeff s Patterson
Loading...
so i need a unit that does 2 zones, i don't have a way to make one zone work and the run will be longer than 50 feet, one area is 192 sqft, one is 96 sqft other is about 300 sq ft. the 300sqft is service by a 14x20 return and a 4 x12 output from the main air conditioner for the house, we can seem to get the 300 sqft area cool or warm enough. I am adding the first 2 spaces mentioned first that are in an unconditioned attic that just got flooring and now walls yet
Kyle
Loading...
We have a variety of dual-zone systems for you to choose from. A 50' line should not be a problem for most multi-zones. Give us a call at 270-575-9595 and we can help you find the right product for you.
Masomas
Loading...
My out door unit and wall unit distance is 30ft do you think This distance reduces or does not affect the cooling power
Kyle
Loading...
The length of the refrigerant lines between the indoor air handler and the outdoor condenser should not affect the unit's ability to cool.
Nick
Loading...
any advise on sizing a unit? I want to add one to my attic, which is very hot in the summer. Also do the Mr. Cool units come with anything longer than the 25 foot lines that are precharged? Is there any work around if I want to use a Mr. Cool unit but require more than 25 feet?
Kyle
Loading...
Coupler kits to extend the MrCool DIY line set length beyond 25' should be out very soon (a week or two). They will allow you to connect two lines together. The size you need will depend on where you live and how much insulation you do (or don't) have. Give us a call at 270-575-9595 and we can help you figure out what you need.
Gene Torriente
Loading...
Good afternoon my question is what is the usual electrical wire gauge used to connect the Mr.Cool to my circuit breaker
Kyle
Loading...
That would depend on the particular model of MrCool unit that you're wiring. You should be able to find the specific wiring guidelines in the product installation manual. If not, let us know which model you're trying to install and we can help. You can also call us at 270-575-9595 x300 for installation support.
Anson Biller
Loading...
Love the sense of humor in answering the question. Thanks
Abe
Loading...
Hi, is there a minimum requirement length for a line set? (Only need 7feet). Wasn’t sure if you need a certain amount of coolent between fhe units.
Kyle
Loading...
A typical condenser is usually charged for a specific line set length. Installations that intend to use a length below the charged amount may need to have refrigerant removed. Any good technician can handle this fairly easily.
Jose Caraballo
Loading...
I'm going to need a 50ft MrCool line set, will it come flared and insulated?
Kyle
Loading...
We have 50' lines, but we do not have precharged 50' lines like those that come with the MRCOOL DIY.
Jose Caraballo
Loading...
Can I connect two 25 ft precharged line sets to equal 50 ft.
Kyle
Loading...
No, the precharged lines cannot connect together in that fashion.
don Luis
Loading...
Seriously, can I run a copper line extension to another head on a separate building? These two buildings are adjacent but my easiest and only way right now is to run the line around the entire building and it is about 70 feet total. thanks
Kyle
Loading...
Don, the answer is: it depends on the brand and model. Some units can't go 50 feet, some can go 100 feet or more. Talk to one of our specialists (270-575-9595), and they can make sure you get a mini-split condenser that can handle a 70' line run.
tony
Loading...
I had to cut my line set to 9 feet. Is the unit going to be ok as it is or do I need to remove refrigerant?
Kyle
Loading...
Yes, you will likely have to remove some refrigerant.
Jeff Brown
Loading...
Dan, I'd like to install a recessed or ceiling handler (intended use is horizontal) in the vertical position. I'm doing this because floor or wall mounted handlers in this space would be unattractive. Can that be done without damage to the handler or compromising its functionality?
Kyle
Loading...
Hard to say for sure without a model # to look at. BUT, typically manufacturers design their air conditioner drainage components around how they intend the product to be installed. For example, a mini-split wall-mount air handler is meant to be installed horizontally on a wall. If it is, then all the excess water pools at the bottom where it can flow out of the condensate drain. Mounting a horizontal wall-mount vertically would literally upend that design, and you would have water leaking out the side. Which would be bad.
Copyright © 1988-2024 Ingrams Water & Air Equipment, LLC. All Rights Reserved. Ingrams is a trademark of Ingrams Water & Air.