The technician installed a new AC split without a vacuum pump

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Discussion Overview

The discussion revolves around the installation of an AC split system without the use of a vacuum pump, specifically addressing concerns about the implications of this practice on the system's performance and longevity. Participants explore the necessity of vacuuming during installation, the potential risks associated with air and humidity in the system, and the proper procedures for handling refrigerants and compressor oil.

Discussion Character

  • Debate/contested
  • Technical explanation
  • Exploratory

Main Points Raised

  • Some participants assert that vacuuming is essential during installation to avoid damage from air and humidity, as stated in the AC manual.
  • One participant suggests that if the original poster is unsure about the procedure, they should not attempt it themselves and should hire a qualified technician instead.
  • There is a concern that the system's dryer may have been compromised due to atmospheric gases entering the system without proper vacuuming.
  • Another participant confirms that some oil may be discharged when the refrigerant is evacuated, which could lead to a reduction in the compressor oil level.
  • One participant expresses caution, warning that improper handling could cause more harm than leaving the system as is.
  • A video is referenced, but its content is uncertain, with one participant speculating that the unit might have been under vacuum before air was introduced.

Areas of Agreement / Disagreement

Participants generally agree on the importance of vacuuming during installation and the potential risks of not doing so. However, there is no consensus on the best course of action for the original poster, with some advocating for professional help while others express skepticism about the technician's qualifications.

Contextual Notes

There are unresolved assumptions regarding the technician's methods and the specific conditions of the installation. The discussion also highlights the variability in HVAC practices and the potential for differing opinions on best practices.

Shervan360
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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.
 
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Shervan360 said:
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.
-
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.
 
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Averagesupernova said:
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.)
 
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.
 
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Shervan360 said:
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.
 
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Please see the video, He used the below method instead of a vacuum pump.

 
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.
 

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