What are the Line Set Length Limits for the 27K and 36K Multi-Zone DIY? - Ask the Expert Episode 237

Today's question comes from Charles Dart. "Hey Dan! What are the line set length limits on the MrCool 27K and 36K Multi-Zone DIY systems?"

On any mini split you have got refrigerant lines that connect to the inside air handler and they go outside to the outside condenser. So, there is a maximum length that line can be. A compressor can't push refrigerant like a mile. That would be impossible.

So, every condenser and air handler, whether it's multi-zone or single zone, is going to have a limit.

For the 27K, the total line set length can't be more than 197 feet, which is really far. So, you should be good. However, you can't have a single line set more than 75 feet between each air handler and the condenser. If you need more than that, you're going to have to do something else or move your condenser.

For the 36K, the total line set length can't be more than 262 and the single line set length between each air handler and the condenser can't be more than 75 feet again.

If you have any more questions, please, just ask in the comments below.

22 comments (view/add)
  • John Healy
    John Healy
    Posted on 6/5/2021

    Hello,
    Just curious if maximum line set lengths must include supply + return length or do we only count the length of the supply and return once together?
    Thanks for your advice
    - John

  • Dan Danowski
    Dan Danowski from Ingrams
    Posted on 6/5/2021

    The maximum length relates to the distance between an air handler and the condenser specifically.

  • CJ
    CJ
    Posted on 5/28/2021

    On a dual zone DIY Mr. Cool 27k unit with a 18k + 9k head I want to order a line set of 16' to connect 9k and 25' to 18k but i need an extra 16' to add to the 25' with coupler to 18k head. Do I need to add more refrigerant because of adding the 16' lineset to the 25' second zone? Also when the instructions say to coil extra near condenser, Why? I'm looking to coil extra lineset in attic/insulated of course to make the connections cleaner at the condenser unit. and not coiled behind or serpentine in attic to eliminate coils all together. Can this be done?

  • Dan Danowski
    Dan Danowski from Ingrams
    Posted on 6/1/2021

    You would not need to add refrigerant, since all the DIY lines have their own refrigerant. It should be fine to keep the extra coil in the attic.

  • Tom Dean
    Tom Dean
    Posted on 5/19/2021

    I bought a 4 zone mini split with two line set extensions to give me 2x 50' runs and 2x 25' runs. Is there a recommended order for attaching them to the condenser? Currently i have the longest two at the bottom in slots 3 and 4 and my short run handler (#1) is not cooling properly if any of the others are off, or #4 isn't max cooling its area.

  • Dan Danowski
    Dan Danowski from Ingrams
    Posted on 5/21/2021

    The largest capacity air handler should be connected to zone A. The others can be connected to whichever port works best. The wiring must be connected to the correct block on the outdoor unit matching the refrigerant lines. If you have excess refrigerant line, it may be necessary to add refrigerant to the system. If some units are not working properly and all the electrical, valves, and fittings have been checked and are correct, open, and tight, then a tech with gauges would be needed to see for sure.

  • Jess Morgan
    Jess Morgan
    Posted on 5/12/2021

    What is the meaning of a maximum lateral length of 33 feet between highest and lowest unit? I want to install 3 units from one cendensor, where our max distance between them is 39 feet. Is this ok?

  • Dan Danowski
    Dan Danowski from Ingrams
    Posted on 5/12/2021

    As long as the highest indoor unit is not more that 33 ft above the lowest indoor unit, you will be fine. The 39 ft between units is fine as long as the elevation is OK.

  • Wayne Rost
    Wayne Rost
    Posted on 4/9/2021

    What is the shortest I can cut a line set for a AIRETEMP minisplit?

  • Dan Danowski
    Dan Danowski from Ingrams
    Posted on 4/9/2021

    I'm not familiar with that brand, so I couldn't say. However, they should detail that in the installation manual in the section on refrigerant.

  • HONORIO CRUZ
    HONORIO CRUZ
    Posted on 4/1/2021

    Bought a 27 K condenser with 2- 9K ac, in the future I will add a 12k Ac.
    My question is:
    Can I shorten my refigerant to 8 ft ?
    the other will be at 12 Fl ,
    and the future line at 75 fl .
    Please advice .
    Thanks

  • Dan Danowski
    Dan Danowski from Ingrams
    Posted on 4/2/2021

    The DIY lines are not designed to shortened. They can be lengthened through the use of a coupler kit. We would not recommend cutting a DIY line to shorten it.

  • russell
    russell
    Posted on 1/13/2021

    can i order a 24k 20 seer unit with a 16 foot lineset .also, if you roll the excess lineset should it be horisznal or vertical?

  • Dan Danowski
    Dan Danowski from Ingrams
    Posted on 1/14/2021

    You can get a 16' line set for the MrCool DIY products. The manual recommends you keep the excess coiled and stored near the condenser. It doesn't actually specify horizontal or vertical.

  • JOHN LEMCZAK
    JOHN LEMCZAK
    Posted on 11/25/2020

    What length of line are the units rated for? If I were to install a 12k unit myself can I use a 25' lineset using just the precharge? In other words, without adding refrigerant?

  • Dan Danowski
    Dan Danowski from Ingrams
    Posted on 11/25/2020

    Yes, you could use a 25' line with the DIY 12k. They lines themselves are precharged for the DIY units.

  • William B Bulliner
    William B Bulliner
    Posted on 11/22/2020

    Can more than one inside air unit be on the same line?

  • Dan Danowski
    Dan Danowski from Ingrams
    Posted on 11/23/2020

    No, each would need its own line.

  • Rick Snow
    Rick Snow
    Posted on 11/17/2020

    What's the minimum length you can have on the line set of a 12k Mr. Cool unit?

  • Dan Danowski
    Dan Danowski from Ingrams
    Posted on 11/17/2020

    If you're asking about a DIY system, the shortest line set available is 16'.

  • Charles Dart
    Charles Dart
    Posted on 11/4/2020

    One other note, Dan. I go by Chuck and I do play darts. For years we had a competitive team called......

    Chuck Dart and the Dart Chuckers

  • Charles Dart
    Charles Dart
    Posted on 11/4/2020

    Thank you, Dan!
    Chuck


* All fields required.

Your email address will not be published. Comments will display after being approved by our moderators. Comments may be edited for clarity.