I am considering installing my Mini split system

[WyrTwister]

Originally Posted by pinballlooking

I have never used manifold gauges or vacuum pump. But the rest of the install looks like something I can handle.
Would this work.
Air Vacuum Pump with R134A and R12 Connectors
Vacuum Pump - AC Vacuum Pump w/ R134A & R12 Connectors


how about these gauges?
Yellow Jacket 42001 Series 41 Manifold 3 1/8" Gauges: Amazon.com: Industrial & Scientific

how about this gauge or do you recommend a different gauge?
Fieldpiece SVG3 Digital Micron Gauge (Vacuum Gauge)
Fieldpiece SVG3 Easy View Vacuum Gauge - at the Test Equipment Depot

Not sure , but it sounds like it would consume a lot of compressed air ? I suggest , at the very least , buy the little electric vacuum pump . I bought one by Robinair , at a pawn shop 10 -15 years ago . When I put in the R22 central air system .

My mini split had the same size fitting on the service valve , that the old R12 & R22 systems . My old hoses and Gauges worked , but I had to do some interpretation on the gauge .

I bought a set of hoses and gauges at Harbor Freight , to work on R134a automotive systems . This has been several years ago .

God bless
Wyr

[pinballlooking]

Based on comments and reading I switched to this tool list.

Yellow Jacket 41780 Manifold w/ 1/4" Fittings, Bar/Mpa, R-410A $57.95
Yellow Jacket 41780 Manifold w/ 1/4" Fittings, Bar/Mpa, R-410A
Robinair 15150, 15300, and 15500 VacuMaster Vacuum Pump $136.95
Robinair 15150, 15300, and 15500 1.5, 3, and 5 CFM VacuMaster Vacuum Pump - on Sale at the Test Equipment Depot
Fieldpiece SVG3 Easy View Digital Vacuum Gauge $121.95
Fieldpiece SVG3 Easy View Vacuum Gauge - at the Test Equipment Depot

[WyrTwister]

Originally Posted by pinballlooking

Based on comments and reading I switched to this tool list.

Yellow Jacket 41780 Manifold w/ 1/4" Fittings, Bar/Mpa, R-410A $57.95
Yellow Jacket 41780 Manifold w/ 1/4" Fittings, Bar/Mpa, R-410A
Robinair 15150, 15300, and 15500 VacuMaster Vacuum Pump $136.95
Robinair 15150, 15300, and 15500 1.5, 3, and 5 CFM VacuMaster Vacuum Pump - on Sale at the Test Equipment Depot
Fieldpiece SVG3 Easy View Digital Vacuum Gauge $121.95
Fieldpiece SVG3 Easy View Vacuum Gauge - at the Test Equipment Depot

Looks good , but I would call them to make sure the gauges include hoses . The info on the web site sound conflicting ?

God bless
Wyr

PS Find out if you need to buy vacuum pump oil ? It may not come with any .

A quart would be sufficient . Or , it might be simpler to buy it locally ? I do . $ 10 - $ 15 a quart .

[WyrTwister]

Originally Posted by NiHaoMike

That vacuum pump is good for vacuum bagging, but no good for HVAC work. A freezer compressor would be far superior to that. But for about $150 or so, you can get a reasonably good two stage.

For some reason, automotive gauges and residential/commercial gauges are different. You should be able to get a reasonable deal at a local HVAC store. (I got my pair of Yellow Jacket gauges for under $50 at a local store a few years back.)

A micron gauge is not a requirement, but it can be very helpful. For a one off, doing a pressure test followed by a triple evac gets it done.

You do need some way to purge (if you need to braze) and pressure test, which can be done with nitrogen or CO2. (Propane can be used for purging, but only for the outdoor connections.)

Also note that a common propane torch will not work for brazing. MAPP gas works, but the good stuff isn't made anymore. Nowadays, either oxy-propane or air-acetylene works great. (So does oxy-acetylene, but it's especially easy to overheat the braze with it...) If you wait long enough, you might be able to find an oxygen concentrator for cheap on Craigslist.

I have read multiple warnings about brazing mini splits . Most recommendations were not to . If you do , the recommendation was a gentle flow of dry nitrogen though the lines , to keep air out & prevent oxidation / scale from forming inside the copper , at the point being heated . It was said , due to the small clearances in a small system such as a mini split , they are especially susceptible to such trash stopping stuff up .

My mini split came with flare fittings , as does most of the units I have read about . While I am a little suspicious about leaks with flare fittings , it solves the brazing issue .

I bought metric flare nut / tubing wrenches , a 3/8" drive torque wrench and straight and flare nut 3/8" drive " crows feet " . At Harbor freight .

I bought a small container of Nylog Blue for automotive gasket / o-ring use . Also found a recommendation to use it on mini split flare fittings . It is a slimy , slick , sticky substance . About the consistency of snot . Seems to work ?

I have not found much info on the POE oil used in mini splits ( I have used POE oil in a R12 -> R134a conversion on a car ) . Any one with a catalog # and brand , or a specification ( including viscosity ) , please send the info to me .

God bless
Wyr

[pinballlooking]

Originally Posted by WyrTwister

I bought metric flare nut / tubing wrenches , a 3/8" drive torque wrench and straight and flare nut 3/8" drive " crows feet " . At Harbor freight .

I bought a small container of Nylog Blue for automotive gasket / o-ring use . Also found a recommendation to use it on mini split flare fittings . It is a slimy , slick , sticky substance . About the consistency of snot . Seems to work ?

God bless
Wyr

I bought this same set from Harbor Freight and a bottle of Nylog Blue.

[WyrTwister]

Originally Posted by pinballlooking

I bought this same set from Harbor Freight and a bottle of Nylog Blue.

I ordered the Nylog Blue off the internet . Can not remember where ?

Last used it helping work on my cousin's car A/C .

Seems to work well .

Think they make Nylog Red for R12 systems . Maybe for R22 , also ? Both use mineral oil , but I do not know if they are the same mineral oil ?

God bless
Wyr

[jeff5may]

Flare connections are not hard to do correctly. If you can put together a kitchen sink, with its water supply and drain lines, the first time through, with no leaks, you can do flare fittings. If not, it takes some finesse and/or trial and error to get it right. That's what the nitrogen and soapy water is for.

The main thing to remember with flare fittings, as with most plumbing, is to get everything situated and immobilized before you tighten up the connections. If you have to swedge your own flares, a good tool works MUCH better than a cheap tool. Vibrations or movement of anything after the fittings are tightened is asking for trouble.

[BMR]

Originally Posted by pinballlooking

I bought this same set from Harbor Freight.

Just a heads up that you may find you need fractional, not metric flare and/or crow's foot wrenches. Check your equipment and lineset when you get them.

[pinballlooking]

Thanks, my first mini split will get delivered Thursday. I will check it out then.

[WyrTwister]

Originally Posted by pinballlooking

Thanks, my first mini split will get delivered Thursday. I will check it out then.

Is it coming with a factory made line set ?

When installing the line set , make sure the condensate drain is positioned on the bottom , with a gentle slope down hill .

God bless
Wyr