How to add oil to ac

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Servicing ac. Got the gauges and the pump. Ac is currently holding vacuum. But one problem, the gauge kit did not come with an oil injector. How should I add the oil after the vacuum? I'm guessing add oil into the line and let the can of refrigerant shoot it in? Thanks in advance
 
Buy an oil injector for about $50. Or pay a pro from that much to dour that to do the same. Conley use new oil from a sealed container.
 
You might want to take it to a pro, I bet that system is picky about having a perfect fill of oil and refrigerant.

Are you adding refrigerant to top off a leak?
 
Correct in that you do add it then chase it with some refrigerant yes. You can also just buy pressurized cans with the proper oil and a small amount of refrigerant, but I normally only add oil when I am adding refrigerant due to a leak. Yes, you need a special tool to add refrigerant that way.

I am also sure that you can probably find a Youtube video on this as well.
 
Originally Posted By: oilpsi2high
Pour it directly into the hose before adding freon.

He's already pulled and verified it's holding vacuum, no chance I'd open system at this point...

If you've replaced components(esp compressor), use the 4oz can of oil charge, but if this is a leak fix & recharge a couple ounces should be plenty... A little too much won't hurt anything but may reduce cooling effectiveness...
 
I had to suck it in through the hose while I slightly opened the valve. It wouldn't pour in the hose so I had to use vacuum from the system. I let gravity take it to the bottom of the ac system, then I pulled vacuum again but from the hot side, waited till it fill to 20 hg than opened the cold side. I did it that way so that it can suck mainly from the hot side and not suck out the oil from cold side. It would only hold about 26-27 hg vacuum. After that I filled it up with freon like I normally would. Blows good now. Thanks for the help guys!
 
85 degrees outside. Pressures read 36 cold and 240 hot. Might of added and ounce or 2 too much refrigerant but no more than that but that's ok I guess.
 
Originally Posted By: PhuongFU
It would only hold about 26-27 hg vacuum.


That means you have a leak. If you can't pull a 500 micron vacuum and have it hold at or below 1000 microns you have a leak. You won't read either of those figures on a compound gauge either, so you need a proper vacuum gauge.
 
Take it to a pro and bite the bullet. Oil level is critical and you don't just top it off like engine oil.
 
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Originally Posted By: Lubener
Highly unlikely you need to add oil unless you change one of the a/c components.


Unfortunately muppets tend to just add oil and refrigerant indiscriminately because it's easily available in "blow off" cans. The reality is a slow leak loses almost insignificant amounts of oil. The only time you need to add oil is (as you say) you replace a component, or if you've had a catastrophic failure (like a blown hose).

What you *should* do is charge the system up, let it run at idle for about 15 minutes, pull the compressor and drain the oil into a measuring cup. Check that against the manufacturers spec and add the *specified* qty of oil back into the compressor. Very few people do that unfortunately as it's just easier to squirt oil into a system and tell yourself it'll be ok. Sometimes it even is.

Then again, you should charge your system either by weight, or by calculating superheat and subcooling, but nobody does that either.

I don't mind people doing DIY A/C services if it's done right, but it never is. But hey, it blows cold. Just dumps [censored] of refrigerant into the atmosphere, but we can just "top it off" using cheap cans from autozone.

Sorry for the rant.
 
Originally Posted By: Lubener
Highly unlikely you need to add oil unless you change one of the a/c components.


On one of my cars, oil leaks from the compressor seam seals. I add some oil when I add refrigerant, sometimes.
 
I have and FJC 2732 that I use to add precise amount of oil to the pressurized a/c system.
 
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