Accidentally evacuated A/C refrigerant: What now?

Jan 11, 2019
2
0
Reno, Nv
#1
Opps well first off my water pump went south. Got it fixed and then the heater core went south. Ok so fixing heater core, I jumped The gun and didn't recheck the video, and I undid the bolt connected a/c line to the canister. Yep it shot off coolant about 10 feet high. So now what steps do I
Do to fix mt booboo.
 

Farmergreg

Just a "Web Wheeler"
Supporting Member
Mar 25, 2018
271
258
WC Indiana
#8
You really need to have it serviced by a shop or someone with proper equipment. They need to pull a vacuum on the system to get rid of any air and moisture introduced into the system when it was opened.
I'd be an advocate for buying a harbor freight / or borrowing a vacuum pump. Drawing a vacuum then recharging by weight using a postal scale. Wouldn't even need a set of gauges.
Specs for mine calls for 1.25# (two cans would be 24oz, needs 20oz.

Previously, I had hooked up the gauges and tried to adjust the freon just using the gauges. Finally gave up recovered it and put it back in by weight and it works like a charm.
 

TJ4Jim

TJ Addict
Supporting Member
Dec 9, 2015
1,146
817
Brookings, Oregon
#9
keep in mind that the accumulator (AC canister) stores the greatest quantity of refrigerant oil in the system and you shot it all out. Along with that the accumulator which has a desiccant dryer internally should be replaced. The trick is trying to estimate the remaining oil in the system.
 
Feb 8, 2018
55
92
Fresno, CA, USA
#10
I agree with Tj4Jim. To further elaborate. You can add refrigerant from the cans you can buy in an auto parts store to a system that has not been opened up. (small, slow leak or a slow loss in pressure) . However if the system has been opened by disconnecting or opening a line, air and moisure will enter the system. If you do not purge it, that moisture will condense and cause corrosion throughout the whole system. Also air will be in your lines when you service it. There is nowhere for that air to go. You will never get the full amount of refrigerant you need.
Think about like bleeding brakes. That air in the system takes up space. It needs to be purged.

Btw, I am a licensed AC tech.
 
Last edited:

Farmergreg

Just a "Web Wheeler"
Supporting Member
Mar 25, 2018
271
258
WC Indiana
#12
I agree with Tj4Jim. To further elaborate. You can add refrigerant from the cans you can buy in an auto parts store to a system that has not been opened up. (small, slow leak or a slow loss in pressure) . Once the system has been opened by disconnecting or opening a line, air and the moisture in it will enter the system. Unless it is purged, that moisture will condense and cause corrosion through the whole system. Also air will be in your lines when you service it. There is nowhere for that air to go. You will never get the full amount of refrigerant you need.
Think about like bleeding brakes. That air in the system takes up space. It needs to be purged.

Btw, I am a licensed AC tech.
Completely forgot about the oil loss in the violent release of freon.