Questions for the resident HVAC mini-split expert

vectordawg

Lil-Rokslider
Joined
Feb 3, 2020
Messages
247
Location
Olive Branch, MS
Hey guys, here's the short story. I bought a mini-split online and had it installed in my shed late fall 2020. It's not one of the pre-charged units. Everything was working fine until the following February when the compressor died. They sent me another one and my guy (Danny) came out and replaced it. Again, everything worked fine until late summer when it stopped cooling. Danny came by with a sniffer and found a leak in the head unit. They replaced that too. Now I can't get Danny to come back. He's like every other HVAC guy, covered up with work! I've called two other guys and got no response. This new head unit has been sitting in my garage since September. Here's where I need advice. I guess I have a couple of options. Leave it alone until I've harassed someone enough to come out and do the whole job. Or take it out and try to solder the line set myself then look for someone to charge it. I'd even be willing to buy a vacuum pump and gauges and learn how to do all of it but I still wouldn't be able to get the refrigerant. What say you?
 
Joined
Nov 14, 2020
Messages
1,002
I used to do general maintenance work for the city. Not a refrigeration specialist, but I’ve repaired leaks, replaced maybe 10-15 compressors and charged systems with refrigerant. Even with that set of skills I personally would wait for a tech you trust. It,s not like sweating copper supply plumbing, and proper charging is critical of course.
 
OP
vectordawg

vectordawg

Lil-Rokslider
Joined
Feb 3, 2020
Messages
247
Location
Olive Branch, MS
I used to do general maintenance work for the city. Not a refrigeration specialist, but I’ve repaired leaks, replaced maybe 10-15 compressors and charged systems with refrigerant. Even with that set of skills I personally would wait for a tech you trust. It,s not like sweating copper supply plumbing, and proper charging is critical of course.
Dang! Ok, well thanks for the advice. I guess I'll just keep calling around.
 

Mikido

WKR
Joined
Dec 14, 2020
Messages
714
The unit is replaced, just need it connected to existing lines correct? Nothing to solder, simple brass nut connections. Is the new unit pre-charged?

I’ve learned to do this myself and have done a
Few splits successfully. You can get everything online for not too crazy of an investment. Shoot me a pm for more details if you decide to down this route. But I do suggest having the pro knock it out in a few hours at no cost to you.
 
OP
vectordawg

vectordawg

Lil-Rokslider
Joined
Feb 3, 2020
Messages
247
Location
Olive Branch, MS
The unit is replaced, just need it connected to existing lines correct? Nothing to solder, simple brass nut connections. Is the new unit pre-charged?

I’ve learned to do this myself and have done a
Few splits successfully. You can get everything online for not too crazy of an investment. Shoot me a pm for more details if you decide to down this route. But I do suggest having the pro knock it out in a few hours at no cost to you.
It's not pre-charged. They only sent the head unit this time. When they sent the outside unit yes, that was just brass connections but i don't think the head unit works the same way. I'm leaving it to the pros! Thanks!
 

H'n'F

Lil-Rokslider
Joined
Mar 14, 2013
Messages
249
Location
Wisconsin
I have 25 years in the business. I would leave it to a professional. Sweating copper is an art... You'll want to run nitrogen while you do it so you don't get oxidation inside of your piping that can plug up your expansion valve. You also want to be careful if you have to sweat close to the inside coil so you don't torch the expansion valve... Depending on the model it may very well just be flair fittings. You also need to recover the refrigerant that's left in there so you don't get fosgene gas. I would not attempt this if you are not trained. I wish I had better news but that's my opinion. Best of luck to you, bud.

Sent from my Pixel 6 using Tapatalk
 
Joined
Jan 12, 2021
Messages
713
Location
Upstate NY
Mini splits are all flare connections. No brazing needed. However, you will need a pro to evacuate the system and charge the unit properly with freon. You wont be able to buy the R410 without the epa certification.
 

Mikido

WKR
Joined
Dec 14, 2020
Messages
714
Mini splits are all flare connections. No brazing needed. However, you will need a pro to evacuate the system and charge the unit properly with freon. You wont be able to buy the R410 without the epa certification.
Agreed should all be flared, and if it isn’t, flare it yourself.

There’s r410a cans all the way up to 25lb on eBay with free shipping. No certs needed. It can be easily done by the mechanically inclined. Plenty of YouTube content.
 

bobr1

WKR
Joined
Dec 11, 2017
Messages
363
Hey guys, here's the short story. I bought a mini-split online and had it installed in my shed late fall 2020. It's not one of the pre-charged units. Everything was working fine until the following February when the compressor died. They sent me another one and my guy (Danny) came out and replaced it. Again, everything worked fine until late summer when it stopped cooling. Danny came by with a sniffer and found a leak in the head unit. They replaced that too. Now I can't get Danny to come back. He's like every other HVAC guy, covered up with work! I've called two other guys and got no response. This new head unit has been sitting in my garage since September. Here's where I need advice. I guess I have a couple of options. Leave it alone until I've harassed someone enough to come out and do the whole job. Or take it out and try to solder the line set myself then look for someone to charge it. I'd even be willing to buy a vacuum pump and gauges and learn how to do all of it but I still wouldn't be able to get the refrigerant. What say you?
Yeah, I’d go with the pro. I had thought about doing an install on my own and by the time I would have bought the unit and the equipment to run it, the price difference was minimal. My electric coop was also offering a really good rebate, but it had to be installed by one of their certified dealers. They got it installed in a day. It would have probably taken me 2 weeks. Anyways, the unit ended up having a problem about a month later and just shut off, only reason I noticed was because I woke up to my dog shaking and the house temp being around 50 degrees. The company that installed it was highly recommended and I had to book them to come up but they came out within a day and then decided to just replace the outdoor unit. Which because they installed it was under warranty and didn’t cost me anything. Anyways, I would probably just wait and have some else do it that has better quality tools for the job and has worked on have a lot of experience trouble shooting. Just my 2 cents. Good luck
 
Last edited:
Joined
Jan 12, 2021
Messages
713
Location
Upstate NY
I am usually all about doing things myself however the Freon is controlled by the epa. Environmental protection agency….you can not buy it without a certification. Fines are substantial no matter what eBay says……
 
Joined
Apr 18, 2019
Messages
346
I'll chime in because this is exactly the kind of dumb idea I'd have. I could just buy the tools, learn, do it, and then fix my own mistakes for the next several years. I have done this approach on lots of miscellaneous things. Even helped a buddy do this exact thing. If you want to use this opportunity to learn something new - go for it. You'll learn lots, you can buy new tools, you can figure out how to buy freon from shady guys on Craigslist. But if you just want it to work, just get on the list and pay the man. Get a pro and move on.
 

Stalker69

WKR
Joined
Apr 12, 2019
Messages
1,729
Mini splits are all flare connections. No brazing needed. However, you will need a pro to evacuate the system and charge the unit properly with freon. You wont be able to buy the R410 without the epa certification.
Yep, you don't braze mini splits, none of the ones I have seen any way. Flare fittings should be on there.
 

Mikido

WKR
Joined
Dec 14, 2020
Messages
714
I'll chime in because this is exactly the kind of dumb idea I'd have. I could just buy the tools, learn, do it, and then fix my own mistakes for the next several years. I have done this approach on lots of miscellaneous things. Even helped a buddy do this exact thing. If you want to use this opportunity to learn something new - go for it. You'll learn lots, you can buy new tools, you can figure out how to buy freon from shady guys on Craigslist. But if you just want it to work, just get on the list and pay the man. Get a pro and move on.
Yes but you’ll move on with learning nothing. A lot of satisfaction in being your own mechanic. Doesn’t take much. I agree with 90% of your post though ;)
 
Joined
Apr 18, 2019
Messages
346
Yes but you’ll move on with learning nothing. A lot of satisfaction in being your own mechanic. Doesn’t take much. I agree with 90% of your post though ;)
Absolutely, I just have too many of these ideas and then they start cutting into things I really want to do - like going hunting. It's just another way of saying check your priorities at the start. My ever so patient wife reminds me that while I could "do that thing" it would mean I wouldn't be doing something else.
 

Titan

WKR
Joined
Sep 13, 2016
Messages
570
Location
Texas
Have you compared the cost for all this compared to just swapping everything with a pre charged kit? Or is it under warranty?

In my area the entire diy kit was less than the cost to get a pro to come out and charge a system
 

Stalker69

WKR
Joined
Apr 12, 2019
Messages
1,729
The things you would need other then " normal tools", would be vacume pump, micrometer, and hoses to connect to the unit. The connections on most are not standard U.S. size, they are slightly bigger but I can't think of the size. Most units are precharged for around 100 feet of line set. So if your under that you should be good. Nitrogen to check for leaks in your connections is a very good idea also, so you would need nitrogen tank, a/c manifold, and a nitrogen regulator also.
 

Mikido

WKR
Joined
Dec 14, 2020
Messages
714
The things you would need other then " normal tools", would be vacume pump, micrometer, and hoses to connect to the unit. The connections on most are not standard U.S. size, they are slightly bigger but I can't think of the size. Most units are precharged for around 100 feet of line set. So if your under that you should be good. Nitrogen to check for leaks in your connections is a very good idea also, so you would need nitrogen tank, a/c manifold, and a nitrogen regulator also.
For longer line sets I agree.

For a garage unit, probably just through wall (like 6’ of line), A little top off can is enough. (Assuming the condenser was valved closed before)

I did 2 units like this without problem. When I installed a 3 zone unit with 50’ line sets, i invested in a flaring tool, vacuum, 25lb can of 410 and nitro tank.

While on the topic, lines sets have doubled in cost in just 1 year! Thanks a lot Joe!

We can discuss this all day, but the OP probably has fixed it by now. /end thread!
 

Stalker69

WKR
Joined
Apr 12, 2019
Messages
1,729
6 feet of line set, and unit ( the ones I have installed come pre charged for up to 100 feet) should not need any additional refrigerant! If unit is empty, weigh charge in to manufactures recommendation.
 
OP
vectordawg

vectordawg

Lil-Rokslider
Joined
Feb 3, 2020
Messages
247
Location
Olive Branch, MS
Have you compared the cost for all this compared to just swapping everything with a pre charged kit? Or is it under warranty?

In my area the entire diy kit was less than the cost to get a pro to come out and charge a system
Its all under warranty.
 
Top