HVAC The technician installed a new AC split without a vacuum pump

[Shervan360]

Hello,

The technician installed a new AC split without a vacuum pump. (Gree 24000 BTU Inverter)
Should we drain the refrigerant, do vacuum, and refill the refrigerant?
It is written in the AC manual that we should vacuum during installation.
I read that air and humidity are harmful for the system and the compressor.

 

[Averagesupernova]

Hello,

The technician installed a new AC split without a vacuum pump. (Gree 24000 BTU Inverter)
Should we drain the refrigerant, do vacuum, and refill the refrigerant?
It is written in the AC manual that we should vacuum during installation.
I read that air and humidity are harmful for the system and the compressor.

The short answer is yes.
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The long answer is that since you are asking that question, it tells me you intend to do it yourself. Otherwise you would contact someone who is qualified to do such work, if they exist in your part of the world, which I do not know where that is. If you have to ask if this should be done, it implies to me that you have no idea of how to go about it. The system has to be pulled down with a vacuum pump and at that point the refrigerant (correct amount for the size of the system and length of refrigerant lines) slowly released into the system. Chances are the dryer has already been compromised due the atmospheric gases being pumped throughout the system.
-
I'm going to take a good guess and assume you are way in over your head.

 

[Shervan360]

The short answer is yes.
-
The long answer is that since you are asking that question, it tells me you intend to do it yourself. Otherwise you would contact someone who is qualified to do such work, if they exist in your part of the world, which I do not know where that is. If you have to ask if this should be done, it implies to me that you have no idea of how to go about it. The system has to be pulled down with a vacuum pump and at that point the refrigerant (correct amount for the size of the system and length of refrigerant lines) slowly released into the system. Chances are the dryer has already been compromised due the atmospheric gases being pumped throughout the system.
-
I'm going to take a good guess and assume you are way in over your head.

Thank you, I will not do it. The technician will do it.

Could you please more explain about it?

Chances are the dryer has already been compromised due the atmospheric gases being pumped throughout the system.

Is it true that some oil is discharged when the refrigerant is completely evacuated? Does the oil decrease? (I mean when we want to release all the contaminated refrigerant and put in new refrigerant. I heard when the refrigerant is completely evacuated, some of the compressor oil will be reduced.)

 

[Flyboy]

Correct. Depending on the system, you will pull most of your oil out with the vacuum pump at the same time as you evacuate the refrigerant.

I second Supernova’s call for caution, though. If you don’t do it right, you’re liable to cause more harm than just leaving it alone.

 

[Averagesupernova]

Could you please more explain about it?

No I will not. I am hot and HVAC tech or engineer. I know enough to realize there is a lot more I do not know. At this point the person you hire to do this job SHOULD be able to answer your questions. If not, they are not qualified enough to do the job.

 

[Shervan360]

Please see the video, He used the below method instead of a vacuum pump.

 

[Averagesupernova]

I can't be sure what happened in that video but I have to assume the unit was already under vacuum and he let air into it. At least one of the guys in the video did not appear happy that it happened.