When I was servicing one of these 2 stage compressors, the schematics was pretty interesting, but now seeing what is being done inside mechanically... that’s amazing! Cool engineering for sure! Thank you!
Reuben! You probably worked harder than me or Ben in this video :D Haha carrying those compressors back and forth. It was a really fun project, thank you for joining us and making it all the better!
Hi Reuben. Thanks for the look inside those compressors. In my 34 years in the HVAC business I have found cheap angle grinders last as long as expensive name brand angle grinders. Thanks again.
So good to see younger people taking an appreciation for engineering from the past that everyone takes for granted. I used to try to inspire this in students I taught by giving them the following (tongue in cheek) homework assignment: For tonight, I want you to go home and make a pencil.
@@ReubenSahlstrom Unfortunately disabled now (POTS). Primarily math (6th-Pre-Calculus), sciences (physics, Chemistry, Biology, and 7-9th sciences), and computer programming were what I did at first. But during my career I taught the entire core high school curriculum (including Bible) in Christian schools. I miss it!
schematics for twin single units show direction is changed by reversing run and start - second relay/contactor changes the point power is fed, effectively doing that.
@@ReubenSahlstrom Yup - schematic here: www.manualslib.com/manual/1602774/Carrier-38ydb.html. Low capacity uses a separate contactor which shunts power directly to the start winding. Capacitor current direction is reversed on low, fed into Herm goes out the common. I imagine the windings were specifically engineered to handle reversing run and start. Seems carrier used lots of bristol 2-stage compressors and customers got burned, as if their poly heat exchanger fiasco wasn't enough.
They obviously have two good parents and live by "middle America" values. I looked up the HVAC company and they are in MN, and mom and pop are founder and book-keeper.
Great video Reuben!! Glad I found your channel. My family does HVAC/R work as well in here in Oklahoma so that was really cool to see how everything worked in that compressor. Keep the videos coming! 👍
Hello Reuben you are in good company with Jay and Ben 👍. I've watched Jay channel for a while now and he feels like family for sure he is a very good guy and I subscribed to your brother channel Ben I heard of his channel from Jay. All of you guys are super awesome people god bless you my friend 🙏 good to get to meet you.
Generically that is called a "one way clutch" or a "free wheeling clutch". There are many different types of one way clutches (sprag, ratchet, roller and ramp, ball and ramp, etc) I can't say I have seen that design. Of course we all know that internal combustion engines is identical to pumps (a compressor pump a gas). 4 cycle engine use camshaft actuated poppet valves, while 2 stroke engines use reed valves. Pumps are 2 stroke because they are simpler and cheaper to manufacture. My guess is that there is a different winding to make the motor go backward.
Wow! I didn't realize that two stroke engines used reeds! That's so interesting! How do they exhaust, since an exhaust reed would prevent proper compression?
10:58 That two speed mechanical drive is crazy smart. It would be interesting to measure the two pistons and compute the displacements for stage 1 and 2. Is it split 50/100%, or more like 33/100%. I think the tubular pipes and chamber on top are a type of "muffler" to quiet the pulses in the refrigerant line. 16:25 Old style Whirlpool washing machine motors had windings for two forward speeds and one reverse speed. How many power terminals on that "two speed" compressor? Many single speed compressors have just 3 terminals. 28:30 Looks like there are only 3 wires on terminal block.
Hmmmm that oil should be fairly clear. And in watching this these fellow apparently haven't seen the inside of the compressor. Well a lot of guy don't but it is good they are seeing this. It helps when you are thinking about what is happening when it is running. You always have to think about what the various parts are doing when the system is running. The scroll is obviously upside down with the motor in the bottom
I thought this was as interesting as you 3. Thumbs up. Do more like this! The grinding sound may be due to the debris from the cutting wheel and metal case fragments.
That uni direction "cam" as you were calling it is a sprag gear. They only spin one direction. Also remember all AC motors are three phase motors so to reverse it you'd mechanically or electronically switch any 2 phases.
Interesting! I am so bothered when I don't have the proper terminology to describe what I am seeing. Thanks! Also, I think you're confusing single phase and three phase compressors. This one (and almost all residential AC compressors) is actually a single phase. It has a start capacitor, relay and a run capacitor. Three phase compressors are generally used in commercial applications where three phas power is available.
@@ReubenSahlstrom the capacitor is there to ”fake” the 3rd phase. Think about it for a moment. th-cam.com/video/YiZgXq11lHQ/w-d-xo.html Also Look at the manufacturer info on the Unit you got that compressor out of. Their literature will have a diagram with the switching mechanism/ device in detail. I'm curious at how they chose to Reverse the motor to achieve the second stage if not by swapping windings to reverse the magnetic field of the motor.
I appreciate the videos yall did, now going to watch bens video. ive been doing hvac a while and never seen inside a compressor...pretty cool stuff thanks
Probably be a good idea too wear ear protection after cutting for extended amount of time 😂 love the videos thank you for sharing I cut a small 1/3 hp reach in reciprocating compressor open the other day and gives a much better idea of how it’s put together and how it all works
You tore apart a perfectly good comp. the reversing is done externally by contractors which change cap connection to the winding. Or if this is 3 phase it is done by swapping two leads to the com via contractors
Yeah it was perfect mechanically, but after testing the external start and run components, it still wouldn't run. We talked to Comfort products and they diagnosed it as having a bad internal connection or something with the motor.
@@ReubenSahlstrom I am reluctant to disagree with Comfort Products but I will. There should be 3 power leads at the external terminal box. If that is true, and the comp will run in one direction ok then all is well internally. The external circuit is at fault. The motor would probably never have a separate winding for reversing operation when it can be done so easily externally. However even tho I understand motor winding very well there may be some strange case where the mfr has a strange winding and maybe this would be a case for that since the required power on low stage is exactly 1/2 of the 2 stage configuration. I would then expect that there would be additional terminal connection for the addition winding (maybe one more terminal)
That's an interesting observation! I still have a lot to learn. The motor would not work in second stage cooling, so for some reason the higher amp draw and increase in work load is what somehow prevented it from starting. What causes an electric motor to lose power? If the windings short somewhere, but don't trip the breaker would it cause the motor to be weaker?
@@ReubenSahlstrom Yes, turn to turn shorts in the windings will diminish the motor capacity to turn the load and not cause a breaker to trip. I lean towards a mechanical problem. Can you tell the mode and the number of terminals on this compressor?
Yay 1k! Good job I'm happy I subscribed this was a nice video. Although I don't understand how the two stage aspect worked. Can you make it into a homemade generator?
Guys, this is not a two stage compressor! It's a one stage compressor, wit two cylinders. In order to be a two stage, one cylinder's intake has to take air (or whatever is being compressed) from other cylinder's outtake, which is not the case here.
Guess again! This is a two stage compressor for Refrigerant, and pumps using two cylinders in one direction and one in the other. It's pretty impressive engineering, watch the video and you'll understand what it's doing, or at least see that we didn't go saying things with zero knowledge. Thanks for expressing your concern, even though you were mistaken, because I sometimes make mistakes and like to be corrected.
Ok, the thing is, i don't have to guess again. :) I am not trying to put you down I just want to show you, that you misunderstood the principle of this compressor and probably a two stage compressor in general, which the one in the video, i repeat, is not. The mechanism on the crankshaft, you are refering to, disengages one cylinder, when motor starts rotating in other direction and works on just one cylinder. You guys thought that that is a two stage comp. It is not. I already wrote you in my previous message, try to picture/understand my words: In order to have a two, or three, or it doesn't matter how many stages, compressor, one cylinder has to suply the second cylinder, with already compressed medium (air or whatever) , so the second one achieves much higher pressure, than the first one, because it took compressed air already and not the atmosferic/lower pressure. All you have to do is, check the cylinder head, that you disassembled yourselves and you'll see that the intake manifold (which is only one, on the head) conects on both cylinders! And so does the outtake manifold too! So it makes impossible for one cylinder to pump to the other, because they ARE NOT conected, via outtake and intake. And that is a principle of two, or more stages, compressors. I'm linking you a short video where you can see how they function. At the end of the video is a two stage and just before is a same principle as in your video. One stage. The difference is that yours has two cylinders and function of disengaging one. Probably because of the energy savings, if it doesn't need that much of a pressure or flow in certain mods. Hope I've been more clear this time and that you'll manage to picture what I've been trying to explain. All the best! th-cam.com/video/p9eFYGIsaB4/w-d-xo.html
Very interesting! I feel rude for saying you were wrong so bluntly, and apologize for being so curt. I think I understand the disconnect in our conversation. A two stage compressor for compressing air is quite different from a refrigerant compressor since with air you want volume at high pressure, and with refrigerant you want volume to remove heat. A unit with two stage cooling only brings on the second stage (100%) in the 20% of days that it needs more power, and runs in the lower stage (often 67%) for the other 80% of days. Apearently we are both right, but I was talking about two stage compressors for doing first and second stage cooling, and you were talking about compressors often used for air. It is, as you said for efficiency that this compressor runs with one piston one way, and two the other, thus first, and second stage cooling. Thanks for clarifying! I learned something!
@Reuben Sahlstrom It's no problem. No need to apologize, really! The point would be to gain knowlege. Knowlege is power. Note that it doesn't matter at all, is it for cooling or for air. And no, a two stage air compressor is not quite different from a refrigerant compressor if we are talking about a compressor work principle. On the contrary, the principle is 100% the same! And they are both compresing gasses. One is compressing air (gas) , and the other one is compresing HCFC, or HCF. Which are both gasses too. It's just, that they have effect of cooling, when being compressed and later liquefied, under pressure. And from reading your last post it still seems that you didn't figure it out, or you're refusing to, since you are still talking about stages in a one stage compressor. Did you look at those intake, outtake manifolds and their relation to a cylinder head?? They are resolving this talk/debate and speak for themselves! You just need to look at it. And all this talk is excessive and unneeded.. When you were mentioning those percentages and stages... (You can call them stages, but they are clearly not ) They are like modes. Full mode and saving mode. It is nothing more, than the amount of power being consumed ( electric current ) and the amount of work, being produced, by those two cylinders. It probably saves the energy when it doesn't need that much work, by disengaging that other cylinder. It drops it's production capacity. There's no excess of anything! It just lowers it's capacity. Two stage produces a surplus of a pressure, on the second cylinder! And since you were trying to play a difference card, betwen air and coolant compresors, I'm linking you a pict/scheme, of a refrigerator, two stage compressor, where difference in work principle comparing to your compressor, is perfectly visible. The one on the right is a two stage. It's rotary one in this case, but that is completely irelevant here. Whether it is a piston, rotary or a scroll. The important thing is, how are cylinders/chambers conected! And on the scheme it is clear that the lower cylinder is compressing gas and sends it pressurised to a certain degree, to the upper cylinder's intake. Which is IMPOSSIBLE with your compressor, because cylinders are NOT interconected in a two stage way. They are in two straight lines. Their intakes are together and their outtakes are together. Like so, II And they should be like X. Do a test yourself.... Conect a manometer on a compressor like in your video and measure the pressure. Then find a compressor like in the scheme, a real two stage one and measure it too. The point is, that the compressor from your video will NEVER EVER be able to produce pressure, as high as the two stage. Here's the scheme: ars.els-cdn.com/content/image/1-s2.0-S0306261912008148-gr1.jpg
This was super impressive! The engineering that went into that compressor was seriously awesome.
I know! Crazy!
and now I know why you could never be a comedian :) just kidding.
same, wonder what those exhaust ones are
When I was servicing one of these 2 stage compressors, the schematics was pretty interesting, but now seeing what is being done inside mechanically... that’s amazing! Cool engineering for sure! Thank you!
Reuben! You probably worked harder than me or Ben in this video :D Haha carrying those compressors back and forth. It was a really fun project, thank you for joining us and making it all the better!
Ah yes, but you bought an angle grinder for me! 😂 Thanks! It was such a fun way to spend the Saturday!
I'm happily subscribed to all three of you guys now!
Wow, you know your stuff there, Reuben. Nice video 👍
Thanks! I have a whole lot to learn yet, but I love learning!
Reuben Sahlstrom, That’s all it takes...
Hi Reuben. Thanks for the look inside those compressors. In my 34 years in the HVAC business I have found cheap angle grinders last as long as expensive name brand angle grinders. Thanks again.
So good to see younger people taking an appreciation for engineering from the past that everyone takes for granted. I used to try to inspire this in students I taught by giving them the following (tongue in cheek) homework assignment: For tonight, I want you to go home and make a pencil.
Wow! That is an assignment that would humble and cause appreciation for even the simplest engineering. What sort of educator are you?
@@ReubenSahlstrom Unfortunately disabled now (POTS). Primarily math (6th-Pre-Calculus), sciences (physics, Chemistry, Biology, and 7-9th sciences), and computer programming were what I did at first. But during my career I taught the entire core high school curriculum (including Bible) in Christian schools. I miss it!
Probably a one way clutch between the crank and the piston rod and some kind of camping sleeve..... very interesting.
I always wondered what was inside and how those things worked. Good job illustrating it all and explaining how it functions. It was fun to watch.
schematics for twin single units show direction is changed by reversing run and start - second relay/contactor changes the point power is fed, effectively doing that.
Wow! That makes sense! It just starts it the other way?
@@ReubenSahlstrom Yup - schematic here: www.manualslib.com/manual/1602774/Carrier-38ydb.html.
Low capacity uses a separate contactor which shunts power directly to the start winding. Capacitor current direction is reversed on low, fed into Herm goes out the common. I imagine the windings were specifically engineered to handle reversing run and start.
Seems carrier used lots of bristol 2-stage compressors and customers got burned, as if their poly heat exchanger fiasco wasn't enough.
These are men who are moving America forward with their hard work ethic, no entitlement in their action.
They obviously have two good parents and live by "middle America" values. I looked up the HVAC company and they are in MN, and mom and pop are founder and book-keeper.
Great video Reuben!! Glad I found your channel. My family does HVAC/R work as well in here in Oklahoma so that was really cool to see how everything worked in that compressor. Keep the videos coming! 👍
Hello Reuben you are in good company with Jay and Ben 👍. I've watched Jay channel for a while now and he feels like family for sure he is a very good guy and I subscribed to your brother channel Ben I heard of his channel from Jay. All of you guys are super awesome people god bless you my friend 🙏 good to get to meet you.
I can't believe you didn't disassemble that two way crankshaft 😱
Generically that is called a "one way clutch" or a "free wheeling clutch". There are many different types of one way clutches (sprag, ratchet, roller and ramp, ball and ramp, etc) I can't say I have seen that design.
Of course we all know that internal combustion engines is identical to pumps (a compressor pump a gas). 4 cycle engine use camshaft actuated poppet valves, while 2 stroke engines use reed valves. Pumps are 2 stroke because they are simpler and cheaper to manufacture.
My guess is that there is a different winding to make the motor go backward.
Wow! I didn't realize that two stroke engines used reeds! That's so interesting! How do they exhaust, since an exhaust reed would prevent proper compression?
10:58 That two speed mechanical drive is crazy smart. It would be interesting to measure the two pistons and compute the displacements for stage 1 and 2. Is it split 50/100%, or more like 33/100%. I think the tubular pipes and chamber on top are a type of "muffler" to quiet the pulses in the refrigerant line. 16:25 Old style Whirlpool washing machine motors had windings for two forward speeds and one reverse speed. How many power terminals on that "two speed" compressor? Many single speed compressors have just 3 terminals. 28:30 Looks like there are only 3 wires on terminal block.
very informative. thankyou.
Hmmmm that oil should be fairly clear. And in watching this these fellow apparently haven't seen the inside of the compressor. Well a lot of guy don't but it is good they are seeing this. It helps when you are thinking about what is happening when it is running. You always have to think about what the various parts are doing when the system is running. The scroll is obviously upside down with the motor in the bottom
I thought this was as interesting as you 3. Thumbs up. Do more like this! The grinding sound may be due to the debris from the cutting wheel and metal case fragments.
That uni direction "cam" as you were calling it is a sprag gear. They only spin one direction.
Also remember all AC motors are three phase motors so to reverse it you'd mechanically or electronically switch any 2 phases.
Interesting! I am so bothered when I don't have the proper terminology to describe what I am seeing. Thanks!
Also, I think you're confusing single phase and three phase compressors. This one (and almost all residential AC compressors) is actually a single phase. It has a start capacitor, relay and a run capacitor. Three phase compressors are generally used in commercial applications where three phas power is available.
@@ReubenSahlstrom the capacitor is there to ”fake” the 3rd phase.
Think about it for a moment. th-cam.com/video/YiZgXq11lHQ/w-d-xo.html
Also Look at the manufacturer info on the Unit you got that compressor out of. Their literature will have a diagram with the switching mechanism/ device in detail. I'm curious at how they chose to Reverse the motor to achieve the second stage if not by swapping windings to reverse the magnetic field of the motor.
You should not talk about electrical if you don't know, maybe go get a job working on Motors and you learn
I appreciate the videos yall did, now going to watch bens video. ive been doing hvac a while and never seen inside a compressor...pretty cool stuff thanks
Glad you found it interesting! We had a lot of fun making the videos!
Benjamin brought me here. I want to see some ear, mask, and long sleeve shirts next time. Just speaking from personal experience.
Really cool guys!
Probably be a good idea too wear ear protection after cutting for extended amount of time 😂 love the videos thank you for sharing I cut a small 1/3 hp reach in reciprocating compressor open the other day and gives a much better idea of how it’s put together and how it all works
You tore apart a perfectly good comp. the reversing is done externally by contractors which change cap connection to the winding. Or if this is 3 phase it is done by swapping two leads to the com via contractors
Yeah it was perfect mechanically, but after testing the external start and run components, it still wouldn't run. We talked to Comfort products and they diagnosed it as having a bad internal connection or something with the motor.
@@ReubenSahlstrom I am reluctant to disagree with Comfort Products but I will. There should be 3 power leads at the external terminal box. If that is true, and the comp will run in one direction ok then all is well internally. The external circuit is at fault. The motor would probably never have a separate winding for reversing operation when it can be done so easily externally. However even tho I understand motor winding very well there may be some strange case where the mfr has a strange winding and maybe this would be a case for that since the required power on low stage is exactly 1/2 of the 2 stage configuration. I would then expect that there would be additional terminal connection for the addition winding (maybe one more terminal)
That's an interesting observation! I still have a lot to learn. The motor would not work in second stage cooling, so for some reason the higher amp draw and increase in work load is what somehow prevented it from starting. What causes an electric motor to lose power? If the windings short somewhere, but don't trip the breaker would it cause the motor to be weaker?
@@ReubenSahlstrom Yes, turn to turn shorts in the windings will diminish the motor capacity to turn the load and not cause a breaker to trip. I lean towards a mechanical problem. Can you tell the mode and the number of terminals on this compressor?
One way one of the cylinders free wheels and the other way both cylinders are controlled by crank shaft
Yay 1k! Good job I'm happy I subscribed this was a nice video. Although I don't understand how the two stage aspect worked. Can you make it into a homemade generator?
I suppose you could if you had enough time! 😂
The cat just chillin lolol
1:15 *WEN* are you going to open yours Reuben? I get what you were saying!
What about the 2 stage scroll
What is the difeective area if the compressor is loos compression
wut
You guys should cut apart a compressor from a cheap former fridge. I am told some cheap compressors only have one crankshaft bearing.
Good job kids
Sounds like some good erik satie music
I'm cutting one open tommrow😊😊😊😊
Cool! Just for fun or in a class?
@@ReubenSahlstrom just for fun !!!! I just graduated trade school a few days ago ! I have my epa universal
@@Hvac-dude Fun! I like doing stuff like that. You should start up your own channel, that would be a fun first video.
@ReubenSahlstrom it sure would be !!!!
Part 2
Guys, this is not a two stage compressor! It's a one stage compressor, wit two cylinders.
In order to be a two stage, one cylinder's intake has to take air (or whatever is being compressed) from other cylinder's outtake, which is not the case here.
Guess again! This is a two stage compressor for Refrigerant, and pumps using two cylinders in one direction and one in the other. It's pretty impressive engineering, watch the video and you'll understand what it's doing, or at least see that we didn't go saying things with zero knowledge. Thanks for expressing your concern, even though you were mistaken, because I sometimes make mistakes and like to be corrected.
Ok, the thing is, i don't have to guess again. :) I am not trying to put you down I just want to show you, that you misunderstood the principle of this compressor and probably a two stage compressor in general, which the one in the video, i repeat, is not.
The mechanism on the crankshaft, you are refering to, disengages one cylinder, when motor starts rotating in other direction and works on just one cylinder. You guys thought that that is a two stage comp. It is not.
I already wrote you in my previous message, try to picture/understand my words:
In order to have a two, or three, or it doesn't matter how many stages, compressor, one cylinder has to suply the second cylinder, with already compressed medium (air or whatever) , so the second one achieves much higher pressure, than the first one, because it took compressed air already and not the atmosferic/lower pressure.
All you have to do is, check the cylinder head, that you disassembled yourselves and you'll see that the intake manifold (which is only one, on the head) conects on both cylinders! And so does the outtake manifold too!
So it makes impossible for one cylinder to pump to the other, because they ARE NOT conected, via outtake and intake. And that is a principle of two, or more stages, compressors. I'm linking you a short video where you can see how they function. At the end of the video is a two stage and just before is a same principle as in your video. One stage.
The difference is that yours has two cylinders and function of disengaging one. Probably because of the energy savings, if it doesn't need that much of a pressure or flow in certain mods.
Hope I've been more clear this time and that you'll manage to picture what I've been trying to explain.
All the best!
th-cam.com/video/p9eFYGIsaB4/w-d-xo.html
Very interesting! I feel rude for saying you were wrong so bluntly, and apologize for being so curt.
I think I understand the disconnect in our conversation. A two stage compressor for compressing air is quite different from a refrigerant compressor since with air you want volume at high pressure, and with refrigerant you want volume to remove heat. A unit with two stage cooling only brings on the second stage (100%) in the 20% of days that it needs more power, and runs in the lower stage (often 67%) for the other 80% of days. Apearently we are both right, but I was talking about two stage compressors for doing first and second stage cooling, and you were talking about compressors often used for air. It is, as you said for efficiency that this compressor runs with one piston one way, and two the other, thus first, and second stage cooling. Thanks for clarifying! I learned something!
@Reuben Sahlstrom It's no problem. No need to apologize, really!
The point would be to gain knowlege. Knowlege is power.
Note that it doesn't matter at all, is it for cooling or for air. And no, a two stage air compressor is not quite different from a refrigerant compressor if we are talking about a compressor work principle.
On the contrary, the principle is 100% the same! And they are both compresing gasses.
One is compressing air (gas) , and the other one is compresing HCFC, or HCF. Which are both gasses too. It's just, that they have effect of cooling, when being compressed and later liquefied, under pressure.
And from reading your last post it still seems that you didn't figure it out, or you're refusing to, since you are still talking about stages in a one stage compressor.
Did you look at those intake, outtake manifolds and their relation to a cylinder head?? They are resolving this talk/debate and speak for themselves! You just need to look at it. And all this talk is excessive and unneeded..
When you were mentioning those percentages and stages... (You can call them stages, but they are clearly not ) They are like modes. Full mode and saving mode.
It is nothing more, than the amount of power being consumed ( electric current ) and the amount of work, being produced, by those two cylinders. It probably saves the energy when it doesn't need that much work, by disengaging that other cylinder. It drops it's production capacity. There's no excess of anything! It just lowers it's capacity. Two stage produces a surplus of a pressure, on the second cylinder!
And since you were trying to play a difference card, betwen air and coolant compresors, I'm linking you a pict/scheme, of a refrigerator, two stage compressor, where difference in work principle comparing to your compressor, is perfectly visible.
The one on the right is a two stage. It's rotary one in this case, but that is completely irelevant here. Whether it is a piston, rotary or a scroll. The important thing is, how are cylinders/chambers conected!
And on the scheme it is clear that the lower cylinder is compressing gas and sends it pressurised to a certain degree, to the upper cylinder's intake. Which is IMPOSSIBLE with your compressor, because cylinders are NOT interconected in a two stage way. They are in two straight lines. Their intakes are together and their outtakes are together. Like so, II And they should be like X.
Do a test yourself.... Conect a manometer on a compressor like in your video and measure the pressure.
Then find a compressor like in the scheme, a real two stage one and measure it too.
The point is, that the compressor from your video will NEVER EVER be able to produce pressure, as high as the two stage.
Here's the scheme:
ars.els-cdn.com/content/image/1-s2.0-S0306261912008148-gr1.jpg
More of a variable load. Some units have 2 compressors and are true 2 stage.
Burned oil I guess so
I'm 999!
Subscribed because your brother asked!