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Mitsubishi mini split not working - basics needed

My daughter and son-in-law just bought an older home in the Minneapolis area. It has a 10-year old Mitsubishi mini-split with 3 wall-mounted heads. Their first attempts at using it resulted in only room temp air being blown out. They had a salesman come to the house for a consult and he wanted to sell them a complete new system.

I've worked on auto A/C and it seems there are some similarities. I suggested that the system has a leak somewhere and that a technician should be able to evacuate the system and determine the location of the leak. Because the compressor was sitting at an angle on the dirt outside the house (no foundation or concrete pad, just on the dirt), I suspect the leak may be in the piping coming into the compressor. Anyway the tech could find the leak, fix it and re-charge the system and they should be golden. Of course if the leak is more difficult to fix then that's a different story.

But my assumption is it obviously has a leak. And I'd further assume if the leak is found and fixed the system could be re-charged and the rest of the system should work (heads, compressor, etc.) Comments? Suggestions?

They also told me that they have three remotes but when they turn on any one of the heads all three heads turn on. I thought that sounded weird but thought I should ask.

Any tips on helping them find a qualified mini-split tech in Minneapolis? I am doing this over the phone with no prior experience with these systems.

Thanks.

Comments

  • GW
    GW Member Posts: 4,989
    edited May 29

    Super bummer I hope they can get their ac back online soon

    there are two types of leaks- easy to find and miserable to find. It can be very time consuming.

    it can be a bad connection, a leaking line set, a leaking wall unit. Outdoor units extremely rarely leak.

    It may not be a leak at all.

    not all companies have the energy to chase these problems.

    Hopefully they can find a good technician!

    Gary Wilson
    Wilson Services, Inc
    Northampton, MA
    gary@wilsonph.com
    Big Ed_4
  • Kaos
    Kaos Member Posts: 653

    Sometimes the challange is the system has been sitting with no refrigernat for a long time. If moisture made it into the system, even if you fix the leak, you will have issues down the road.

    If the system is still holding some pressure, just low on refrigerant, a fix might be possible.

    Replacing a 3 zone system is not cheap, so at least a reasonable effort to find the leak is worth it but only if the system still has pressure.

    HVACNUT
  • HVACNUT
    HVACNUT Member Posts: 6,786

    If the outdoor unit shifted a good amount, it could have effected the flares. I can't offer anyone by you, but I'm sure there's lots of HVAC contractors in and around the Cities. You mentioned salesman, so nobody even put gauges on it? Checked diagnostic codes?

    It's a roll of the dice. Even if its an easy fix, you dont know if anything else is wrong. (I thought there was full disclosure rules when selling.) An easy repair is 2-3 hours with a triple vac. And refrigerant isnt cheap. 10 years isn't young. No warranty on parts. Is there a sticker from a service company on the outdoor unit? They might have a history. It might not even be a refrigerant issue.

    And obviously the outdoor unit needs to be secure. Leveled and raised or mounted on a bracket and raised above the snow line. Which is what, about 12 ft. in Minnie?

    Any remote will operate any head, but all 3 at the same time? Are all the walls mirrors?