Air Conditioner commissioned without a vacuum pump & N2?

Click For Summary

Discussion Overview

The discussion revolves around the installation of a split air conditioning system without the use of a vacuum pump or nitrogen cylinder. Participants express concerns about the adequacy of the installation process, particularly regarding the evacuation of lines and potential moisture issues. The conversation touches on technical aspects of AC systems, including pre-charged lines and installation requirements.

Discussion Character

  • Debate/contested
  • Technical explanation
  • Exploratory

Main Points Raised

  • One participant questions whether it is possible to install an AC without a vacuum pump or nitrogen, expressing concern about the technician's capabilities.
  • Another participant asks if the lines are pre-charged or evacuated, suggesting that if not, evacuation and purging are necessary to remove moisture.
  • There is a discussion about whether the system is a mini-split, which may come with pre-charged lines, and inquiries into how piping is handled in such systems.
  • Some participants mention that refrigerant is contained within the outdoor unit and discuss the implications for installation and charging.
  • One participant shares their experience with cryogenic refrigerant systems, emphasizing the importance of gas purity and proper installation practices.
  • Another participant suggests contacting the manufacturer for installation requirements, indicating that they have reached out but have not received a response yet.
  • Concerns are raised about potential compressor damage if proper installation procedures are not followed, leading to a reconsideration of the need for a vacuum pump.

Areas of Agreement / Disagreement

Participants express varying levels of concern about the installation process, with no consensus on whether the absence of a vacuum pump and nitrogen is acceptable. Multiple viewpoints regarding the necessity of these tools and the implications for system performance remain unresolved.

Contextual Notes

There are uncertainties regarding the specific type of AC system being installed, the definition of pre-charged lines, and the manufacturer's installation requirements. Participants also note the importance of proper evacuation and purging to prevent moisture contamination.

rollingstein
Messages
644
Reaction score
16
I bought a new home AC (split; 1.5 ton) and the tech the company sent to install it didn't seem to have neither a vacuum pump nor a N2 cylinder in his kit.

I am leery. Is it really possible to install an AC without these items? Can he do a reasonable job evacuating the lines & leak testing any other way?

I've stalled the tech for the moment. Should I be looking for a better tech?
 
Engineering news on Phys.org
Are the lines 'pre-charged/evacuated' with some sort of air-tight connection? If not then you need to evacuate/purge the lines to get the moisture out.
 
Last edited:
nsaspook said:
Are the lines 'pre-charged/evacuated' with some sort of air-tight connection? If not then you need to evacuate/purge the lines to get the moisture out.

Not sure about the lines. I will check. But the refrigerant is inside the out door unit itself. No external charging from a cylinder.

That's not what you meant by "pre charged lines" though, is it?
 
insightful said:
This isn't a 'mini-split' system, is it? They can come with pre-charged lines.:

How do they do the piping in a pre charged system? Is it possible to bend & join pipes that contain refrigerant inside them?
 
rollingstein said:
Not sure about the lines. I will check. But the refrigerant is inside the out door unit itself. No external charging from a cylinder.

That's not what you meant by "pre charged lines" though, is it?
They might use pre-charged lines systems with a small auto purge of the gas on the specialized“quick-lock” while the connection is made. Most of my experience is with He cryogenic refrigerant systems where gas purity is pretty important at 10K or lower so all of our lines are purged and pre-charged before installation using special connectors.
 
Gas-charged lines can be bent. Have you contacted the manufacturer for installation requirements?

Edit: Pre-charged lines seem to be rare. In all cases, most of the refrigerant comes in the outdoor unit.
 
nsaspook said:
Most of my experience is with He cryogenic refrigerant systems where gas purity is pretty important at 10K or lower

Sounds fancy. May I ask what kind of systems you were cooling so low?

Or would you have to kill me if you told me? :smile:
 
insightful said:
Have you contacted the manufacturer for installation requirements?

I have. But I haven't heard back yet. This is an LG unit.
 
  • #10
rollingstein said:
Sounds fancy. May I ask what kind of systems you were cooling so low?

Or would you have to kill me if you told me? :smile:

It's nothing fancy, mainly for cryogenic pumps for vacuum systems.
 

Similar threads

Does a "heat pump" not spew HFCs like an "air conditioner"?
  • · Replies 7 ·
Replies
7
Views
2K
HVAC The technician installed a new AC split without a vacuum pump
  • · Replies 6 ·
Replies
6
Views
5K
Problem set with air conditioners and thermodynamics
  • · Replies 5 ·
Replies
5
Views
3K
Find the Best Hand Vacuum Pump for Long-Term Use
  • · Replies 6 ·
Replies
6
Views
3K
Chemically regenerating my auto's catalytic converter?
  • · Replies 19 ·
Replies
19
Views
9K