Propress for HVAC Lineset - reliable connections??

[branimal]

I need to install 11 indoor mini split units and 4 outdoor units in a multifamily building. The lineset is being fished down wall cavities. There are some turns involved that I won't be able to accomplish with a bender. My plan is to make the longest runs possible and then connect the lineset. Initially my plan was to braze all the connections. 1/2", 3/8" and 1/4" lineset. Using a nitrogen purge to prevent oxidation.

I've read brazing 1/4" lineset is risky b/c the line could easily get partially clogged with filler metal. Another issue someone brought up was mini split lineset wasn't intended to be brazed. Reasons being 1) mini's dont have filter dryers. 2) It could mess up the TXV 3) The warranty would be voided.

Then I started reading about the Milwaukee press tool . Milwaukee part # 2922-20. And RLS three jaws - 1/2, 3/8, 1/4" (HVAC specific). It's not a cheap setup. The press tool can be had for $1400 USED. And the jaws are $330/ per NEW. I don't mind spending the money, b/c I might have to install mini splits in the future. And if I don't I can sell it to the next guy.

Are pressed HVAC connections reliable? Anyone have experience with them? Another alternative is to use flare connections.

What do you guys think?

Thanks!!

 

[karoc]

I been out trade for while now, but with refrigerants now the pressures I believe could be well over 500psi on high side or higher. Keep in mind that evap coils with or without txv had capillary tubes. Don’t know if press fitting will work or not with those kind psi. HVAC industry has made lot advancement since I use to run roads so I’m out touch

 

[65’Comet5.0]

Hospital I work at has had a few VRF systems installed using them and so far after two years of operation no issues.

 

[pcmeiners]

Never used a press on.....

Do you have your EPA 608 cert to work on Minisplits? If not it is unlikely you can get warranty coverage from most manufacturers. As is if you get warranty coverage manufacturers do not pay for labor, require a licensed pro to check out an issue, and you pay for it; also learn to pray you get a part sent out fast if a warranty is honored . Basically a warranty ain't worth much.
As to bending tubing 1/4 and 3/8" within a stud cavity is usually no issue.

If you need to braze have sufficient nitrogen flow, it should be no issue .

"mini's dont have filter dryers. " Who stated that?

"It could mess up the TXV 3) The warranty would be voided."

With proper nitrogen shielding you do not get any particles to mess anything in the system.

 

[rlitman]

...With proper nitrogen shielding you do not get any particles to mess anything in the system.

He didn't say particles. He's talking about how it's easy to over use the brazing rod until filler closes the 1/4" line. And sure, it's possible, but it would take really overdoing it to make that happen.

 

[brewchief]

There are several brands of refrigeration press fittings available and they take different jaws, just an FYI.
We already had the press tools for plumbing fittings so we just needed the jaws. We don't use a lot of press fittings on refrigeration but do on some occasions, typically in a place that we don't want to braze for one reason or another. To date we have had zero problems, prep on the tube ends is important and can take a bit of time to get right.

 

[danski0224]

Are pressed HVAC connections reliable?

Not sure if enough time has passed to give a proper answer. Does reliable mean lasting through the installer warranty, or the lifetime of the equipment?

Plumbing press fittings commonly fail due to improper installation/prep. This is the problem- installer complacency.

Anyone have experience with them?

The company I work for uses them frequently, although I do not always understand why one job gets them and the other doesn't. Installation is on commercial jobs, so it is almost always rigid copper, not a lineset. Lineset tubing is not always round.

The lineset is being fished down wall cavities

Good luck with that, if the building is finished.

Another alternative is to use flare connections.

This would be way cheaper.

There are powered flaring tools.

You will need a torque wrench.

Flare needs to be made properly so it doesn't leak.

There are some turns involved that I won't be able to accomplish with a bender.

Probably need to approach the installation sequence differently.

I've read brazing 1/4" lineset is risky b/c the line could easily get partially clogged with filler metal.

Must have been written by those that do not know what they are doing.

 

[brewchief]

Personally on a mini split I would use flare fittings, you need a quality flare tool and torque wrench anyways for the connections at the units so why switch up in the middle?
I have a black max flare kit that makes perfect flares almost every time, it has a go nogo gauge to verify the finished fitting.
I have 2 or 3 other(and sometimes more expensive) flare tools and none of them can make repeated flares like the black max kit I have.
I use a black max torque wrench as well, dumbest looking torque wrench I've seen as the business end is an adjustable wrench but it works very well.
I also have mighty bracket that holds the indoor head in place and lets you make connections before hooking onto the wall, not really needed if going straight out the back and making connections outside but if hooking to a buried lineset in the wall it's a nice piece.

 

[pcmeiners]

"He didn't say particles"

He did not say particles but that is what you get with oxidized copper not using nitrogen as an inert shield, which is what manufacturers are worried about.

As far as bending issues, I ran 5 lineset within walls/joints with multiple bends with bending mandrels from a kit from EZbend, some of the bends would not be possible with most other benders.

https://www.supplyhouse.com/Easyben...0n_sP92JlvVrCwiSJTtq8sXiYoWaPNJ4aAqHpEALw_wcB

 

[branimal]

Do you have your EPA 608 cert to work on Minisplits? If not it is unlikely you can get warranty coverage from most manufacturers. As is if you get warranty coverage manufacturers do not pay for labor, require a licensed pro to check out an issue, and you pay for it; also learn to pray you get a part sent out fast if a warranty is honored . Basically a warranty ain't worth much.

I did get my EPA 608. I dislocated my shoulder in September and needed to keep myself occupied. I'm not sure having the cert will qualify me for a warranty. That seems to be a open debate. I feel like having the cert is like passing a drivers permit test. I have de minimus actual know-how on how to install a mini.

"mini's dont have filter dryers. " Who stated that?

I read that in a forum. Maybe HVAC talk.

He didn't say particles. He's talking about how it's easy to over use the brazing rod until filler closes the 1/4" line. And sure, it's possible, but it would take really overdoing it to make that happen.

I've been sweating copper pipe for 6 years. Is the process similar enough that the skills pass over?

I have a black max flare kit that makes perfect flares almost every time, it has a go nogo gauge to verify the finished fitting.
I have 2 or 3 other(and sometimes more expensive) flare tools and none of them can make repeated flares like the black max kit I have.
I use a black max torque wrench as well, dumbest looking torque wrench I've seen as the business end is an adjustable wrench but it works very well.

You like the black max more than the Hilmor or Yellow Jacket flaring tools?

For the torque wrench I was going to use a Harbor Freight 3/8" drive socket wrench with crowfoot adapters. Maybe that's not such a great idea. I'm willing to spend the money on tools to get this right.

The lineset is being fished down wall cavities

Good luck with that, if the building is finished.

branimal said:
There are some turns involved that I won't be able to accomplish with a bender.
Probably need to approach the installation sequence differently.

It's a three family attached building in New York. (My neighbors to the right and left share a wall with me).

Third floor is finished. 2nd, 1st, basement are being worked on. So very easy access. My plan is to fish the lineset to the 3rd floor from the basement. And then punch out 20 feet horizontally to the outdoors. I'm not sure how to make that change in direction without making a joint.

The other issue I ran into was the basement foundation walls sit proud (inwards) of the frame of the house. Meaning the top floors are 20ft wide but the basement is maybe 18ft wide. So fishing straight up from the basement might not be possible.

Thanks for all the responses guys!

 

[pcmeiners]

"I did get my EPA 608. I dislocated my shoulder in September and needed to keep myself occupied. I'm not sure having the cert will qualify me for a warranty."

Having the cert will keep you legal, (unlikely anyone cares), will get you gas/parts at an HVAC counter but you are correct most manufacturers have stipulations which may get them out of honoring a warranty. I say "may" because many of the stipulations will not hold up if the attorney general of the state is contacted. Even if they do eventually honor a warranty, it may take time to get them to honor it, no less your part may take months to deliver.

The lineset is being fished down wall cavities .

If the walls are finished it is near impossible to snake insulated linesets. Far easier to open up the cavity to run the lines. Even if you could do the near impossible, the lines expand and contract which would make noises; the lines need to be attached to studs every couple of feet.

 

[danski0224]

I'm not sure how to make that change in direction without making a joint.

Save yourself the aggravation and cut the drywall or plaster.

 

[rlitman]

...I've been sweating copper pipe for 6 years. Is the process similar enough that the skills pass over?...

Kind of, in that there is some skill transfer. If you use the 15% silver rod and some of the proper flux, then yeah, it sort of wets out and wicks a little like lead free solder. But it also needs enough heat to visibly glow in a dark room, and it blobs more than it drips, so if you get overzealous, it is possible to fill up a 1/4" OD tube, where that would be impossible with solder (it would all just drip out).

With a little practice, it is actually possible to line up (slightly overlapping) all of your rod stubs on a heat-proof surface and torch them back into a single long rod again. That's not happening with solder, so yeah, it's quite different.

Anyway, there is not enough skill transfer that I would suggest your first "paying job" to also be your first learning experience. Practice on some samples and by the time you get through a handful, you should be good.

 

[brewchief]

You like the black max more than the Hilmor or Yellow Jacket flaring tools?

For the torque wrench I was going to use a Harbor Freight 3/8" drive socket wrench with crowfoot adapters. Maybe that's not such a great idea. I'm willing to spend the money on tools to get this right.




It's a three family attached building in New York. (My neighbors to the right and left share a wall with me).

Third floor is finished. 2nd, 1st, basement are being worked on. So very easy access. My plan is to fish the lineset to the 3rd floor from the basement. And then punch out 20 feet horizontally to the outdoors. I'm not sure how to make that change in direction without making a joint.

The other issue I ran into was the basement foundation walls sit proud (inwards) of the frame of the house. Meaning the top floors are 20ft wide but the basement is maybe 18ft wide. So fishing straight up from the basement might not be possible.

Thanks for all the responses guys!

I have a hilmor flare tool and it will not make a flare that will pass the go no go gauge more then 25% of the time. Black max is good probably 98% of the time.

Some of the flare nuts I've run across on mini splits don't seem to be either standard or metric, nothing fits good except and adjustable wrench.

If I understand you have to go up or down with the linesets in a wall and then go about 20 feet outside? If so I completely understand the need for a joint. If at all possible place that joint in an accessible area so it can be inspected in the future if there is ever an issue. I wouldn't have any problem using a flare coupling in that spot.

 

[chinboys]

I would use Harris StayBrite 8 to braze the swag joints you make to connect the line sets.
Just flow enough nitrogen, watch your heat and use juste enough solder to flow the joints.

Too many of us over heat the joints to braze the silver filler.
This new stuff is stronger, the connection, than the copper pipe or tubing.

 

[danski0224]

StaBrite 8 is solder, not braze. No need to use nitrogen.

There may be municipal requirements to braze the connection, and other stuff.

The OP needs to review local codes.

 

[branimal]

• I'll use flares to make my connections located behind access panels. Ordering the Blackmax flaring tool with the go/no go gauge. (BFT850K)
• Opening the walls so I can strap down the lineset

Thanks for all the responses. I'll post an update on the progress.