Precharged Minisplit?

[ceosam]

I've got a Mitsubishi Mr. Slim minisplit and I just read about it having "precharged" lines. Is it possible I can install this sucker myself or whats the story? I've read conflicting things... I'm fairly handy and have a vacpump. My lineset is 25ft.

 

[the gnome]

I've a 2013 mr slim
they didn't have pre-charged line sets then I knew of.
maybe they do now...?

Fredrich breeze are precharged MS's and lines are vac'd
it's pretty much a plug-n-play thing
just hook up the electrical from what Ive heard


others may have more input

 

[Coconutz]

You dont want anything with quick connects. You want it soldered together.
Even the units with the screw together connector at the outdoor unit are an issue overtime.
I have a daikin that we had to solder at the indoor unit, but the fucking outdoor connects leaked a little after being tightened almost enough!

 

[M1XW311]

i was under the assumption that the unit comes precharged for your lines and unit

...and the lines are under vacuum...?

 

[ceosam]

this thread is old.

most units come charged for 25ft of lineset, you need to use a vacuum pump to make sure there is no moisture in the lines before releasing charge from the condenser unit

 

[the gnome]

btw...whats the prob with the quick connects?
I have em,they are great time saver, mine work flawlessly,
3rd coast has them and he loves em and is getting another unit.
I'd say user error is probably the biggest factor when probs arise.
Ive yet to see threads piling up with *bad quick connect* stories?

btw dumbnutz if your going to give hvac advice,
you need to know what your F...g doing 1st.
you don't, and people can fuk up their expensive AC units with you telling peeps to cut-n-braze on a mini split w/410A
without telling them to run nitrogen when they do it. ......

If you braze/weld the pipe without running nitrogen through it while brazing, copper oxide will form inside the pipe. This black soot will most likely clog/restrict the refrigerant metering device, hampering performance. R-22 systems weren't as much of a problem because the r-22 can dissolve the oxide to an extent. The oxides can play hell with a 410-a system though.

and on the subject of flair nut fittings, not "screw together connectors" nutz..
tightening them "almost most enough" yeah, it will leak.
there's a torque setting thats in the install manual,
use a torque wrench to do it properly .no wonder your unit leaked.
more on the flair nut fit'gs

You probably have a lineset with r-22 type flares...I've seen a few people , including myself have problems with it. I just went a bought a $300, 410-a/mini-split specific tool set because I was tired of fucking with it. The new flare tool works perfectly. Trying to match up shallow flares with deep nipples just doesn't work out.

on the flair fitting probs, all internet sites seem to offer generic linsets for mini's.
unless your getting factory OEM linesets you can have probs, even then the flairs can be an issue.
another thing if your having flair fittings leaking they have to be torqued.
here's more advice from a local Hvac tech

@ the guys having problems with the flare fittings. I'd hazard a guess that your lines have the wrong type of flare on them. Most techs still use their old flare tools from the days of r-22. The new 410-a systems require a special, 410-a specific flare tool, which produces a deeper flare than the the older tool. If the flare isn't done with the proper tool, the fitting will almost certainly leak. Also, the fittings NEED to be torqued with a torque wrench. Too loose and they leak, too tight and the flare will crack...and leak. Using a dab of refrigerant oil/lubricant on the face of the flare is a good idea too.

more

I too learn about shitty flared ends on "generic" line sets. You know, the ones ACwholeslaer, goductless, Kingersons, etc, sells.
I went out and bought a proper 410A tool and have never looked back. Now I automatically cut off the flares and use the flare tool; proper depth/height etc is built in. No guess work and perfect flares every time.
It pays to invest in the proper tools, especially for those of us who just can't have a tec do any installing...
The only line sets I've found that are consistent are the ones from Mitsubishi. Don't know about other brands of line sets though as I only use Mr. Slims'

 

[Snauseberry]

^^ excellent info