Minisplit install lessons learned

[BMR]

Originally Posted by AC_Hacker

So, the big question is... now that your confidence level is in full turbo mode, what's your next project?

Next project is to install the used electric hot water heater someone gave me and disconnect the tankless coil in my oil boiler. Then I will shut off the boiler in the months it is not needed, which I am hoping to have extended by at least a month on either side of the season with the mini split.

[pinballlooking]

Thanks for posting what LG model did you install?
I am about to try my hand at installing a mini split in the next few weeks. I have been reading lots until then.
Can I pressure test with CO2 I have a 20 lbs cylinder with gauges.
Mark

[Xringer]

Originally Posted by pinballlooking

Thanks for posting what LG model did you install?
I am about to try my hand at installing a mini split in the next few weeks. I have been reading lots until then.
Can I pressure test with CO2 I have a 20 lbs cylinder with gauges.
Mark

Do not use CO2.. At room temp liquid CO2 will turn into 800-900 PSI gas.
If it gets warm outdoors, the pressure will go much higher.
If it gets cold, the pressure will drop..

Too much pressure and no accuracy at all.




The best reason for using nitrogen, is just in case your pressure test pushes the
test gas into the outdoor unit..
You can get nitrogen at your local paintball shop..
Using dry Scuba tank air would be way better than CO2..

[pinballlooking]

Thanks. I just talked with the guys that fill my CO2 tanks. He said he will rent me a Nitrogen tank for just the cost of the gas used.
I am going to order these gauges.
Amazon.com: Uniweld RHP400 Nitrogen Regulator with 0-400 PSI Delivery Pressure, CGA580 Inlet Connection and 1/4-Inch Male Flare Outlet Connection: Home Improvement
Does that look good?
Mark

[BMR]

Originally Posted by pinballlooking

I am going to order these gauges.
Uniweld RHP400 Nitrogen Regulator with 0-400 PSI Delivery Pressure, CGA580 Inlet Connection and 1/4-Inch Male Flare Outlet Connection
Does that look good?
Mark

That's the same set I got. Worked just fine.

I'm not sure the manifold gauge set you listed earlier comes with hoses. You should double-check. You'll also need a 5/16 adapter for the mini split service port threads, or a hose with the correct fitting.

[pinballlooking]

You are right it did not come with hoses but they were pictured 
This is the one I am thinking about getting now.
Yellow Jacket 41780 Manifold w/ 1/4" Fittings, Bar/Mpa, R-410A
Thanks I have a 5/16 adapter ordered.

[WyrTwister]

My old hoses that fit R22 & R12 systems fit the low pressure service valve on my Comfort Aire mini split . Is that size SOP for mini splits ?

God bless
Wyr

[AC_Hacker]

Originally Posted by WyrTwister

My old hoses that fit R22 & R12 systems fit the low pressure service valve on my Comfort Aire mini split . Is that size SOP for mini splits ?

God bless
Wyr

I forget what kind of refrigerant you mentioned...

But in the trade, they call the R22/R12 fittings "regular fillings". They are actually 1/4" flare fittings that have been adopted (as in adopting stray cats) for refrigeration work. The practice now is that just about every gas has a designated fitting.

I like 'regular' fittings, since I can get 1/4" flare parts at the local hardware store, and this makes it really easy to cobble up all kinds of useful refrigerations hacking tools.

-AC