#^@#$ Kinked mini split line

[BigMike62]

I installed a Senville 24k BTU mini split for my 740 sqft garage. I was being so careful and went so slow but still kinked the larger copper line. I thought if I rerouted the lines I could make it reach but it was too short once I cut out the kink. Since I removed 5 feet, I had some to play with. Now I'm thinking do I braze the lines, order a new line set, but then it hit me. Flare the cut end, make a new line to go from the compressor to the cut line and flare both ends and join then with a flare union.

Now the problem. I couldn't find a 7/8" flared union anywhere so I had to order it online. $25 for the union and another $25 for 2 day shipping but it will be here in 1 day most likely. I completed everything except joining the two lines which I hope I can do tomorrow. Then I'll pull a vacuum and let the freon loose. This is my first HVAC install and overall, it's been easy. Just hope everything works when I fire it up.

 

[rust in the eye]

Swage and solder

 

[PoorUB]

Swage and solder

Or use a sweat coupling.

 

[Jackfre]

You are missing a step. If you flare the repair or silver solder it you need to run a high pressure nitrogen test prior to running your vacuum pump. If SS’ing you need the nitrogen backing to prevent sugaring the interior of the joint…absolutely. As you state, you will repair and hit it with a vacuum pump. the VP will conceal a small leak that over time will show, first in the heat mode, as it runs at much higher pressures in heat. Should you use the flare coupling make sure it is accessible. Don’t ask me how I know this. It was really unpleasant. Also practice, practice, practice on some of the off-cut tubing until you can be certain of making a perfect flare.
A question for you. Did you re-flare the ends of the line set you bought? Reason I ask is I know folks who assume the line set if “factory flared” and okay to use. The only thing the manufacturer of the line set flares for is to keep the plastic plug on the ends to prevent air and moisture into the interior. It will not hold operating pressures. I have a friend who bought a 36 quad system and a 36 dual. He borrowed all my tools but used the factory line set flares. Every joint leaked and he is still two yrs later trying to straighten it out.

 

[BigMike62]

You are missing a step. If you flare the repair or silver solder it you need to run a high pressure nitrogen test prior to running your vacuum pump. If SS’ing you need the nitrogen backing to prevent sugaring the interior of the joint…absolutely. As you state, you will repair and hit it with a vacuum pump. the VP will conceal a small leak that over time will show, first in the heat mode, as it runs at much higher pressures in heat. Should you use the flare coupling make sure it is accessible. Don’t ask me how I know this. It was really unpleasant. Also practice, practice, practice on some of the off-cut tubing until you can be certain of making a perfect flare.
A question for you. Did you re-flare the ends of the line set you bought? Reason I ask is I know folks who assume the line set if “factory flared” and okay to use. The only thing the manufacturer of the line set flares for is to keep the plastic plug on the ends to prevent air and moisture into the interior. It will not hold operating pressures. I have a friend who bought a 36 quad system and a 36 dual. He borrowed all my tools but used the factory line set flares. Every joint leaked and he is still two yrs later trying to straighten it out.

Thanks for the information.

I reflared the ends at the compressor side. I attached a picture of the two flares I made to join. The fitting didn't show up so now I'm wonder what to do. I haven't been able to reach the company I ordered it from so might have to dispute the charge and find another vendor. I got some cheap swage tools from Amazon that came today. I have extra 5/8" pipe that I can swage and solder. The problem is that I have no idea how to fill this thing with nitrogen. Also, how do you fill something with nitrogen that you're soldering together? The compressor is still sealed with freon. The indoor unit was filled with nitrogen which was let loose when I attached the line set.

 

[fillister]

You said 7/8 tube, possibly you can find flare seals in that size.​

Amazon $16.00​

FlareSeal® Model MSP-0406 Leak Free SAE Flare Connections - Refrigerant Leaks Refrigeration, HVAC, Ductless, Schrader Valve or Mini Split Applications (1/4", Mini Split Pack - (2) 1/4" and (2) 3/8")​

 

[BigMike62]

You said 7/8 tube, possibly you can find flare seals in that size.​

Amazon $16.00​

FlareSeal® Model MSP-0406 Leak Free SAE Flare Connections - Refrigerant Leaks Refrigeration, HVAC, Ductless, Schrader Valve or Mini Split Applications (1/4", Mini Split Pack - (2) 1/4" and (2) 3/8")​

The tubing is 5/8" but the nuts are 7/8"

EDIT: After a trip to a few hardware stores, I realized the flare union size is the size of the pipe. The flare nuts have 7/8" stamped on them which is why I thought I needed a 7/8 flare union.

 

[Wiz02]

Thanks for the information.

I reflared the ends at the compressor side. I attached a picture of the two flares I made to join. The fitting didn't show up so now I'm wonder what to do. I haven't been able to reach the company I ordered it from so might have to dispute the charge and find another vendor. I got some cheap swage tools from Amazon that came today. I have extra 5/8" pipe that I can swage and solder. The problem is that I have no idea how to fill this thing with nitrogen. Also, how do you fill something with nitrogen that you're soldering together? The compressor is still sealed with freon. The indoor unit was filled with nitrogen which was let loose when I attached the line set.

Check out AC Service Tech LLC on YouTube. Here's a link on brazing with nitrogen vs silver solder vs brazing without nitrogen

Some interesting comments on "non corrosive" flux and StayBrite8 in the comments section.

Also do a search for mini split flares, just do your diligence on who to trust.

 

[fitter30]

Kinked line. You tube video just type it in " kinked copper line"

 

[Jackfre]

You need a nitrogen cylinder and a regulator. You connect using your gauge lines to the condensing unit. You Probably need the adapters to go from your gauge hose to the service valve on the unit. You can work on the line-set evaporator side without letting the refrigerant into the system. Once you flare or solder the line set and your flares are pristine and connected you do the high pressure N. Test and see if it holds. If you does, you can then connect your vac pump evacuate and then you releases the refrigerant into the system. You really need to spend a bunch of time on you-tube and get a better check-out before going forward.

 

[BigMike62]

After watching the video, I decided to order a new line set for $120. I'll start at the compressor and make the bend as the pipe there has groove swirls to make it easier to bend. The connected point the indoor unit is straight.

Thanks for all of the help!

 

[BigMike62]

New line set came and I spent 2 hours carefully bending and connecting it. Torqued each fitting to spec. Pulled a vacuum and let the freon into the system.

WE HAVE A/C IN THE GARAGE!