This video is the ultimate guide to air conditioning compressor basics. Bryan explains how an A/C compressor works, what an air conditioning and refrigeration compressor does, and what it needs to do its job.
Compressors come in all sorts of types, including reciprocating, scroll, rotary, screw, and centrifugal compressors. All types increase the pressure of vapor refrigerant; they all decrease the volume to increase the pressure, which causes it to move.
Many compressors are powered by electrical plugs (often made of Fusite), which connect to the motor on the inside. Compressors generally have three different designs for varying degrees of accessibility: hermetic (sealed), semi-hermetic (bolted), and open-drive (where the compressor is separate from the motor).
Compressors can only compress vapor, not liquid. We check the superheat to make sure we’re only sending fully vapor refrigerant to the compressor; sending liquid to the compressor can damage it. The suction gas temperature is also important to ensure that the compressor head is being cooled adequately (for refrigerant-cooled compressors) and to make sure the mass flow rate is good.
Mass flow rate also plays into compression ratio, which is the ratio of absolute discharge pressure to absolute suction pressure. The compression ratio is a measure of how efficiently a compressor is pumping; too much compression indicates a lack of efficiency (such as through re-expansion).
Compressors have oil inside their crankcase, and a small amount of oil circulates with the refrigerant. Oil control is very important, as compressors have bearings that need to stay lubricated. If liquid refrigerant gets into the compressor, it can cause foaming and oil loss, which can lead to increased mechanical wear and possible premature failure over time. When liquid refrigerant migrates to the crankcase during the off cycle, it can create a flooded start that causes a lot of oil loss. (Crankcase heaters, liquid line solenoid valves, and hard shutoff TXVs can all help prevent flooded starts.) Overheating can also cause the oil to break down.
When the compressor increases the refrigerant pressure, it also increases the refrigerant pressure because the molecules move more quickly in a smaller space. For the most part, the heat content stays the same (with the exception of some minor contributions, such as from the motor windings) despite the temperature increase.
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Excellent. Many people don't realize that compressors are cooled by the proper refrigerant charge, using that coolant on the return or suction line, to keep the compressor from overheating. Thus destroying the oil and parts within the hermetic or semi-hermetic compressor. Very well explained. Thank you for all of your superb videos.
Compressor split I always looked at.
Please help me understand my Copeland compressor. It is a scroll compressor from 2000. There’s another cylindrical tower next to it it’s probably 1/4 the size of the compressor but similar in appearance. What is this other piece of hardware do and what is it called? You have a great videos thank you
Amateur question here: if the compressor is working and winding resistance is correct, how do you know if compressor is mechanically bad? Will it not be able to reach condensing pressure? If so how will you be able to differentiate between mechanically bad compressor and low refrigerant charge? Would you just have to weigh out refrigerant then refill system and condemn compressor?
Please constructive feedback only, no supertech comments. I admitted up front it’s amateur question .
Great stuff i am a new apprentice this videos have been great
Very professional, thank you Sir.
So what kind of pressure are we talking about? Say I want to build a fridge compressor. What pressure and flow rate should I aim for?
I have been in Germany.
The style of your teaching reminds German colleges .
Great job ,
You are true professional. Please continue 👍
Where do i find the tonage on a home ac comptressor
My man.
SUPER EXPLANATION.
Lost me on the increases temperature and not heat statement when you immediately went to it "losing that heat". Think you meant increases in temperature means it increases in heat density, meaning amount of heat contained within something . But spot on none the less.. just a way of wording things that had me questioning my definitions of things.. 🙂
Soooooooo glad I found this channel !!
why the compressor fail frequently on dry cleaning machine pleas suggest the beast solation
Thank you 😊
Nice information thanks bro keep it up
I love how you explain step by step 👏🏾, very knowledgeable , big help thanks
I did not have much science in high school but years later I have had the oppertunity to gain insights of physics of fluids and their properties of change from one state to another . Brian you must have had alot of school science to grasp and understand the laws of physics . You do a great job of presentation in this video , and not lecture over our heads of your topic on compressors . I gather more and more information and evolving skill each time I watch your videos
Cheers
I would love to hear your thoughts on l.a.c.'s I am producing a custom 40 ton wall mounted unit and we are having trouble with out l.a.c. especially on startup.
Hi i am looking for a compressor for a 2 door side byside kennmore refridegarator.
Really well-explained video of the process. Not in the industry but I found it quite fascinating. Thank you.
Ok..so this is Compressors 001.
Any HVAC person should know this from the start.
Very cool! Ha. No pun intended, but I really thought the more scientific explanation was great! Thank you.
i still have a troubleshooting card on compressors from way back in school there are so so so many possible reasons for failure of a compressor your have to be a genius to remember them all , !
thank you very good
Thank you!
Very nice video. Very explanatory. Thank you sir
I thought it be cool to make an off grid refrigeration system based on an open Drive compressor. Then you could have a DC motor spin it and be able to swap it with a gas engine, propane engine. Whatever you want. Control system would be difficult but totally possible. Love the videos by the way learning a lot
Very insightful! Very clear explanation of principle of VC Cycle without using any diagram!
Nice job and video
Dear sir very good video!!!
In my country Greece all speak about compressors with Hp and this make a lot of misunderstanding!!!Is that way in your country ???What is your opinion about that?
How can I get to contact u
I have swapped my live and neutral line. Did I damaged my compressor. Thanks for your help
I like the way u put things out ! simple , clear and plain. Thx u sir .
Thank you very much. Very helpful and educational video
Great job
👍👍💪💪
how much PSI does the compressor produce
Nice work on all your videos. You folks do a great service to our excellent industry. Thank you.
May i ask? Can the R410a Compressor using R22 refrigerant? And what the side effect of that?
I wish i had these videos when I studied. Great work!
@4:34
Do you instead mean "then the compressor is going to do more work and run hotter"?
Great video! I'm in school right now and every little bit of knowledge helps!
Nice explanation
Nice video, 🇮🇳
Open drive seen a lot in your car
In Vehicle air conditioning they use a variable displacement compressor, axial piston design. The piston is driven by a wobble plate or swash plate.
Very well Explained. Thanks!
“These compressors are designed to compress vapor”. Do they make a compressor for liquid?🤬
Check out my VRF Installation video 🤗 https://youtu.be/-fGGnO5b_oY