Flare Fitting 90 Degree Elbow
We have installed a Mitsubishi multi-position air handler MVZ-A18 as part of our ducted HVAC system. The fittings that protrude from the front of the unit that are attached to the coil – one gas 1/2″, one liquid 1/4″, have a male flared fitting. The fittings are welded in place and come straight out the front of the unit. The multi-position is very compact except for these fittings which protrude 3″ from the front face. By the time one makes the 90 degree flared fitting with copper and bends the tubing, one is 6-7 inches out from the front. That makes it hard to locate the unit in a closet because the gas lines stick out so far. The total depth of the unit without fittings is only 21″.
Is there any fitting available that would allow us to make the 90 degree turn with a brass fitting of some type and then make the copper flared tubing connection in 1/2″ an 1/4″. My HVAC installer says he has searched everywhere for one and hasn’t been able to find a solution.
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Replies
You could try these guys:
http://muellerrefrigeration.com/products/flare-fittings-flanges/45-flare-fittings/connectors/
Another option would be McMaster Carr, which a quick look DOES seem to show some fittings which might work for you:
https://www.mcmaster.com/tube-fittings/for-use-with~refrigerant/45-flared-fittings-for-copper-and-brass-tubing-9/
McMaster Carr is happy to sell in small quantities too. They are an excellent source for oddball stuff when you only need a few of something. I have ordered from them often.
Bill
I looked at the unit here
https://www.gemaire.com/mitsubishi-mvz-a18aa4-m-series-multi-position-air-handling-unit-18k-btu-for-mxz-multi-zone-heat-pump-system-mvza18aa4
and it looks like it came with the 90 deg fitting. If yours is missing then just flare the copper and cut it, slip on the flare nut, then solder on a copper 90 onto the stub and subsequent tubing.
Just following up on this thread to see if any of the suggested solutions worked. I'm installing a MLZ one-way concealed cassette and the frame out that was done doesn't allow room for straight connectors (my fault). I'd like to turn the liquid, gas and condensate line up 90 degrees to clear the ceiling joists. Joists are only 2x6 and I'm not able to notch or drill to access the connections horizontally.
Since the pipe cover can be cut to accommodate "superinsulation" I don't see why the top section can't be modified to allow a closer 90 elbow to the unit.
Any experienced insight would be helpful.
Thanks!
Mechanical supply houses will have refrigeration fittings in addition to the links I mentioned a few years back. Keep in mind that refrigeration lines tend to be "oddball" sizes like 7/8", so they do NOT work with the usual fittings that are geared more towards water and gas lines. The other option is to use a tubing bender to form bends in soft copper lines, if you have sizes that will fit in the smaller benders.
Bill
Try IMS Bolt or Blackhawk Supply. I've gotten many unusual flare fittings from there. Sounds like a bend might not work in your case, but a set of spring-type tube benders for pipe that small costs like $15, so you could give it a shot. 1/4" is very easy to bend by hand, 1/2" is pretty easy.
Even a perfectly done flare connection is a small leak, I would avoid adding extra flares if possible. You can also get one of those poly bender kits, these are plastic rods that fit inside the refrigerant line, which make bending near existing fittings easier.
Even if you do go for flares, you probably only need it for the vapor line as the liquid lines can be bent pretty tight with a decent bender.
Overall, I would try to figure out how to do the connections as is, maybe drill or notch the rafters if possible or re-frame for a larger opening. Kinked tubing right at the unit is bad news.
Your HVAC tech can also braze on a copper elbow to do the tight bends. This avoid any flare connections there just make sure they back purge with nitrogen when brazing and clean the brazing flux afterwards. I've had refrigerant lines pinhole from left of flux before.