why does an a/c system have to be "evacuated" after replacing a condenser?

Answer 1

the system has to be evacuated before you replace the Condensor other wise if you open the system to replace the condensor and the system still has freon in it you will vent the freon to the atmosphere which is illegal and you can hurt yourself from the high pressure gas/liquid escaping.
After you replace the condensor you have to pull a vacuum on the AC system to "Boil Out" all moisture and air from the system. The Longer you pull a vacuum on the system, which I guess you can call it "evacute" the better it is for your system. preferrable 30 to 45 minutes is the standard time depending on the Humidity in your particular area.
If the system has been open for any peroid of time, You must replace the reciever/dryer or accumulator.
If you do not pull a vacuum on your system, all you are doing is trying to add freon to a system that has air and moisture in it and your system will not be as efficient as it should be and the added moisture in your system will ruin it.

Answer 2

Not only it should be vacumned out, you should also replace the 'dryer' as well.

AC systems work on the concept that when Freon Gas expands it absorbs heat. If the system is not vacumned out then air is left in the system to prevent a full 'filling' of freon.

Also there is always humdity in the air and this water will liquify in the compressor portion of the AC system. This water will then cause permenant damage to the AC system. The dryer is designed to capture all what vapors and prevent this damage.

Refilling and AC consist of....
1. Replacing dryer.
2. insure a good Sealed system
3. Evacuate the air out of the system. For auto AC you should vacumn the system for at least 30 minutes. Larger systems require longer.
4. Refill with the proper to type freon and insure proper high and low side pressures.

Good luck and I hope this helps!

Answer 3

Air conditioning systems have a special gas (usually Freon) inside the piping, which is essential fot he system to work. There can be no other gas present inside the system, ot it won't work properly. When the piping is opened (as it must be to replace a condensor), air gets into the system. This air must be removed, and the system refilled with Freon for it to work again. The "evacuation" is the process of removing the air.

Hope this helps.

Answer 4

Yes it does have to be evacuated. The reason is because you have to remove all the moisture from the system. Moisture in an A/C system will cause it to corrode from the inside and it will also effect the efficiency of the system (not as cold as it should be).

Answer 5

The system has to have a coolant such as freon in it to work. Any air in the system prevents it from working properly. All the air has to be pumped out of the system, or evacuated, before the freon is put in.

Answer 6

ya gotta check for leaks after installing a new art in the system...+ ya gotta get the old oil and the air outta the lines...would you want to drink some coffee and then just fill up with water right after without washing out ur cup??

Answer 7

Yes it does, all air must be removed and the system put under a vacuum before the new refrigerant is added.

Answer 8

if your condenser is immediately replaced does one still have to replace the accumulator, my local dealership said the accumulator did not have to be replaced just because your system has been opened, help, its hot in Texas

Answer 9

I agree with most of these answers. However the air we breathe has containment's in it, and this does not work well in AC.

Answer 10

to make sure there are no air pockets and the system is fully charged.