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I believe they now sell other size lines and extensions.

I got hung up on the excess line set idea and did a full DIY install of a non-DIY model mini-split. I bought, borrowed, and rented a lot of tools, spent a lot of time researching and learning. I really wish I went with the DIY model.

Despite that lesson, I may do it again when I finish my attic space, but this time I'll add copper line brazing to the list.




Was there anything beyond the extra time/effort that made you regret going with a non-DIY model? I’m considering doing the non-DIY in next year or so.


No, not at all. I enjoyed it but my wife had a different expectation of completion date than I. My advice is to get the tools, don't shortcut, so that you have confidence at each step.

Stuff I had already specific to HVAC:

-R-410a manifold, gauges, and hoses.

Stuff I went out and bought:

-Nitrogen tank pressure regulator and hose for HVAC.

-Mandrel pipe bender

-Flaring tool

-Micron vacuum gauge

-A slightly better copper pipe cutter and deburring tool.

Stuff I rented/borrowed:

-Vacuum pump from Autozone. Free. It was plenty big enough for a minisplit.

-Full nitrogen cylinder rental from Airgas.

Things I'm glad I did:

-Used a wall mount instead of a pad for the compressor unit. Unit stays clean.

- Pressure testing with nitrogen. It's worth the money and effort to know up front it doesn't leak.

-Followed a more thorough procedure for vacuuming/drying which involves vacuuming down several times and flushing with nitrogen. I got a much better vacuum after subsequent flushes.


Thanks for the follow up! I understand completely. Somehow my wife stuck with me after more than a few significant home projects with misaligned expectations around completion. Re: wall mounting vs pad. Do you find noise transmission to be a nuisance?


I was on the lookout for it, as it was a concern of mine. I haven't noticed an issue. It's also mounted on an exterior wall of my garage. That wall lacks insulation but has drywall. It may be more of an issue if it shared a wall with a bedroom. The mount has rubber dampeners between the unit and the arms.


As long as the unit is pre-charged, DIY installs aren't that bad. I've done 2 Pioneers at my home. I spent around $150 in tools.


How do you get the pipes through the wall in a pre charged unit? Do they have two pieces connected by a special valve? I’m curious about how they keep the air out of the lines.


Pre-charge has one of two meanings here. Most mini-split units have the refrigerant in the compressor unit. After a complete installation, evacuation, etc, you open a valve to release the refrigerant into the lines.

There are also DIY variants where a fixed line length comes from the factory with either a vacuum or a refrigerant in the line. The lines have metal seals on the fittings that are ruptured when torqued down on the equipment.


Awesome, I’ve been considering installing a few myself but am not sure if that’s silly or not.

I’m mostly curious how these DIY units compare to Mitsubishi, which seems to be what all the installers recommend.




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