Do I need to evacuate my AC?

[taurus_sable]

I think I messed up with a set of manifold gauges. Initially my AC was just low on r134a based on the manifold gauge readings.

I made a mistake of opening the lower side. the AC leaked much of r134a out with a 5 psi reading now on low side.

In this case do I need to pay for the evacuation? I'd rather not.

Thanks for help!

 

[crazyoildude]

just add one can of r134 and see how cold it is then if its not cold enough add another one they sell a hose with the gauge on it if it went empty it would be a good idea to evacuate the system just to make sure...

 

[taurus_sable]

I understand it may be best to vacuum it but it would cost me at least $150 to do it in a shop. It's not that I have a huge leak in the system and it is completely. It was my mistake to open the low side and the refrigerant leaked out and had some psi remaining in the system. Theoretically is it ok not to vacuum?

Thank you. me just too poor..

 

[robshelton]

It's always a good idea to evacuate the system anytime you are working on it. That said, as long as you have a little 134 in the system, you should not have let any moisture in. I say refill with R134 and let it go.

 

[KB2008X]

You'll be OK to just add to it, but don't waste anytime doing so and leave the compressor off until you get it topped off.
It may not have looked like it, but you lost a fair amount of oil when the 134 was purged from the system. Be sure to get the big can at WalMart that has some refrigerant oil in it, too. It's an 18oz. EZChill can made by Interdynamics, it sells for about $25. It has the 134, the oil and leak sealer. You don't really need a leak sealer, unless you think you have a leak, but it won't hurt.
If after the 18oz can you still need more, which is possible, then add a 12oz. can of just 134.
18oz with 134 and oil first and 12oz 134 only second. Don't do the 12oz 134 only first.
You'should be aiming for 35psi when you're done. Any more than that and you're asking for trouble on an older system like your's. If after the two cans, you're still shy of 35psi there are smaller 8oz cans of Quick Cool or Cool Boost that you can use.

Keith

 

[tommygunn]

Assuming the pressure never hit zero, there's no opportunity for contaminants to have entered the circuit. I wouldn't worry about evacuating it in that case. It might be worth topping off with a bit of oil though to make up for whatever (dry) freon you add back.

 

[Merkava_4]

Originally Posted By: taurus_sable
I understand it may be best to vacuum it but it would cost me at least $150 to do it in a shop.


You only need to vacuum it if there's moisture in the air. Bringing the system to a deep vacuum
will boil off the moisture. Usually in the summertime, there's very little moisture, if any at all.

 

[taurus_sable]

Much thanks to all! advice noted.

 

[2009Edge]

If you have an A/C three hose, two gage manifold you can "rent" a vacuum pump from Auto Zone. You get all of your money back when you return it. You may even be able to rent the A/C manifold.

The internet can tell you how to use the tools if you don'e know how.

 

[wtd]

You don't really need to evacuate in your situation, it will just take longer to charge since you are not charging into a deep vacuum. I would also not get any refrigerant that has a sealer in it as that stuff can cause problems later on. I also really doubt you lost very much oil when you let the refrigerant out. Most of the oil stays in the compressor, condensor, evaporater, and accumulator.

I would just get straight refrigerant or refrigerant with a few ounces of oil only and then recharge with the correct amount.

Wayne

 

[mechtech2]

If there was some r134a still in it, you do not need to evacuate the system.
If you opened a line or removed a part, that is a different story.