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Well after a little research i found one from inficon that doesnt look too shabby.......

http://www.hvacr-tools.com/mm5/merch...e=VACUUMGAUGES

klienman was the buddy i was talking about....

hes more paranoid about these things then i am lol haha

It seems like my supco vg64 is not very consistant, i can put it on the same set of gauges, pull a vacum twice for the same amount of time and i will get two totally diff readings, i mean its supposed to be consistant right? Its really got me thinkin of buyin another one, something that is a little better.

looking at the specs what makes this gauge so much better then the other??

I have a CPS nothing special i think its a vg2000 or something. anyway its accuracy is +/- 10%. (as is the supco)

this thread could have come at a better time. my buddy and me put his new supco and my guage on just the vacuum pump and other times on the gauges.

they were consistently about 30-100 microns off when still pulling a vacuum but when allowed to stand it was a couple hundred off. his was always higher!

mine would hold around 300-500 standing and his would be 750 to 1100.

so even if i assumed his was off 10% to the low side and mine was off 10% to the high side they still were 100 microns or so off from each other when i think they sould be closer to a middle figure..

anyway this looks to be the same accuracy just looking to see why this is better?

I ve the YJ (x2) and the C&D (x2) the C&D are better then the YJ I, have to rebuild the YJ more often.

This is pretty much the setup I use.
http://www.yellowjacket.com/HVACRPro...&l=2&c=17&p=58

Has anyone had their YJ core removal tool leak yet? Mine actually just broke too. The female part that screws on the port popped off

-Mark

Originally Posted by AHH-COOL

I'm confused, how are you hooking up your vac pump and micron guage if you're not using a manifold? How do you put refrigerant in without letting in air and moisture?

DON'T use a manifold?????????

Originally Posted by beachtech

try to put it farthest from pump. more accurate reading of the system and not the pump

THE BEST PLACE!!!!!!!!! any other place is just a waste of time.

I'm confused, how are you hooking up your vac pump and micron guage if you're not using a manifold? How do you put refrigerant in without letting in air and moisture?

Originally Posted by Tiger93rsl

Will a vacuum pull the core back in when it gets deep enough if your O-ring isn't holding tight? And how about useing those core removal tools under a vacuum, you would think those o-rings they use would leak over a short period of time. And I haven't found away to repalce the o-rings in my C&D core tool. Never mind I forgot about the ball valve. Anyhow not to hijack this thread but does anyone know how to replace those O-rings?

on my robinair valves, unscrew the valve body and the ball will drop out once you get the teflon seat out of the way. Once the ball is out of the way, take the screw holding the lever to the shaft and then the shaft will push into the center where the ball was so you can get at the o-rings on the shaft.

Originally Posted by beachtech

try to put it farthest from pump. more accurate reading of the system and not the pump

you can put it anywhere actually, then when you shut off the pump the gauge will read where your at. Most often there is no place else to put it except right there at the access fittings.

Originally Posted by spark

Which side do you guys connect your vacuum gauge too (suction or liquid)? And does anyone use that vacuum sealant that YJ sells that you put on the fittings?

-Mark

try to put it farthest from pump. more accurate reading of the system and not the pump

The term "breaking with N2" means placing N2 into the system while under a vacuum. I pull my vacuum thru both high and low sides. I insert the N2 into the low side . After the system gets pressurized by the N2, I open the high side to let it out. While the high side is still open, I put some more N2 into the low side. Sounds complicated but is not.

Originally Posted by Gunslinger

When I do my first and second vacuum, When the system is in a vacuum, I put N2 into the system about 50 lbs thru the low side. Then I let the N2 escape thru the high side. Pull vacuum again, use N2 again. Then I pull my final vacuum; when the desired level is achieved, I put refrigerent into the system. You never want to open the system that is in a vacuum to the atmosphere or it will "suck in" moisteure and air.

Hi

How long do you apply the N2 at 50 lbs ?

Are you only pulling vacuum on the high side as the means for the N2 to escape? Or are you bringing the system back up to 50 psi with the N2 and then letting it escape through the high side?
Is that what is referred to as breaking the vacuum with nitrogen?

Thanks

When I do my first and second vacuum, When the system is in a vacuum, I put N2 into the system about 50 lbs thru the low side. Then I let the N2 escape thru the high side. Pull vacuum again, use N2 again. Then I pull my final vacuum; when the desired level is achieved, I put refrigerent into the system. You never want to open the system that is in a vacuum to the atmosphere or it will "suck in" moisteure and air.

Originally Posted by Gunslinger

I pull a vacuum (no cores installed) and purge with N2. Then I pull a vacuum again. I like to see no more raise than 100 after watching the micron gage for 15 minutes. The use of the core removers and N2 make the process much faster.

Hi

When you do your purge after pulling the initial vacuum how much N2 do you suggest using?
Do you bring the system all the way back up into a positive pressure with the N2 ??
Is the N2 purge supposed to help remove moisture?

Also I see in literature where it says to break the vacuum with Nitrogen so does that mean bring the pressure back up in the system to 0 psig or a little on the positive side before adding the refrigerant to the system?

Thanks

Originally Posted by Texas-Tech

Today I ran both 6cfm pumps all day long on a 15 ton split, 2"suction about 120 ft long. When I turned them off I was at 455. We will see in the am what the reading is after setting all night. How much rise would be acceptable and what would it tell me? Could be moisture still in pipe or a small leak,,,,,,,,guess we will see.
The other 3 are finished and held at 500.

Hi

Im curious at how this turned out and curious at how many minutes you guys normally wait to determine if the system is leak free and moisture free.
Especially in the 410A and 404 systems do you guys usually do a couple or more pull downs to get the moisture out of the systems?

Thanks

I use a product called Nylog. I usually put the micron gage on the liquid side; no real reason.

Which side do you guys connect your vacuum gauge too (suction or liquid)? And does anyone use that vacuum sealant that YJ sells that you put on the fittings?

-Mark

Post 58 on the thread that Beach linked to is a pic of my set up.I try to get below 200 microns everytime I pull a vac.On commercial jobs,I will use two pumps on numorous times.