Air Conditioner commissioned without a vacuum pump & N2?

AI Thread Summary
Concerns were raised about the installation of a split AC unit without a vacuum pump or nitrogen cylinder, questioning whether proper evacuation and leak testing could be performed without these tools. The discussion highlighted that while some systems may have pre-charged lines, most refrigerant is contained within the outdoor unit itself. It was noted that pre-charged lines are rare and that proper installation typically requires evacuation to remove moisture. The potential for compressor damage without proper installation techniques was emphasized, prompting a recommendation to consider insisting on the use of a vacuum pump. Overall, the importance of adhering to manufacturer installation requirements was underscored.
rollingstein
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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?
 
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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.
 
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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.
 
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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.
 
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