What Are Pre-charged Line Sets? - Ask the Expert Episode 264

Today is just a general question that we get a lot: “What are pre-charged line sets?”

Most normal refrigerant lines that you’re going to get for a heating and air system or a mini split are empty. They don’t have refrigerant in them. So, when we say pre-charged line set, we mean something specifically like the MrCool DIY lines or the no-vac quick-connect lines for the MrCool Universal. They all have refrigerant in them so that when you connect them, they already have the refrigerant and you don’t have to vacuum the lines or charge the system during the installation. 

So, if you get something like an LG mini split, it’s not going to have pre-charged lines. That would be a conventional installation system. There are some mobile home units like Revolv that have pre-charged lines. 

9 comments (view/add)
  • wayne corbit
    wayne corbit
    Posted on 9/13/2021

    Can a Mr Cool DIY Condenserthat I have (DIY MULTI 3-27HP230) be paired with Olympus air handlers if you remove the DIY valves(on the condenser) and do a conventional vacuum and charge installation. . Will the air handlers communicate correctly with DIY condenser units? The DIY and Olympus looks the same condenser to me except for the DIY valves added to

  • Dan Danowski
    Dan Danowski from Ingrams
    Posted on 9/21/2021

    Would it work? It might. We've never tried, so we can't say for sure. The manufacturer certainly wouldn't approve that kind of installation, but it could theoretically function.

  • Sarah
    Posted on 8/30/2021

    Hi Dan,

    We ordered a Mr. Cool DIY and when we opened the box, one of the caps was off of the refrigerant lines. Is it unusable now? Do you think Home Depot will give us a refund?
    Thanks in advance! I really enjoy your videos!

  • Dan Danowski
    Dan Danowski from Ingrams
    Posted on 9/1/2021

    I can't say what Home Depot will or won't do. That said, I suspect the unit is fine.

  • Martin S
    Martin S
    Posted on 7/22/2021

    Hi Dan, can I disconnect the Quick connect couplers from the indoor unit and re-connect a new line set? If I do, would the couplers be damaged? This unit is from Mr. Cool and the line set I received was the wrong size, it is too short so I need to install a longer line.

  • Dan Danowski
    Dan Danowski from Ingrams
    Posted on 7/23/2021

    Yes, it is possible to disconnect a Quick Connect line. The line should not be damaged if done properly.

  • Michael Dowd
    Michael Dowd
    Posted on 7/21/2021

    I love this Guy, he is very informative and very funny. Thanks

  • Martin
    Posted on 6/22/2021

    Is it true, the state of New Jersey does not allow the installation of pre-charged lines by homeowners? Specifically referring to the Mr. Cool D-I-Y.

  • Dan Danowski
    Dan Danowski from Ingrams
    Posted on 6/28/2021

    We are not authorities on New Jersey building codes. I am personally not aware of any prohibitions like that.

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