Thank you! And thank you for watching!

Thank you! And thank you for watching!

You are very welcome! I'm glad I hope you understand this. That's why I do these videos trying to help the guys out there. Understand how things work and hopefully help make everyone a better technician! I started HVAC in 1979 and I need you guys to pick up the torch. and makes some good money out there! Thank you for watching!

I'm so glad that you do! And I'm glad I could help! Thanks for watching!

Thank you! Understanding unloaders can help you troubleshoot units or figure out what is going on. Thank you for watching! And I'm glad you liked the video!

I'm glad you like the video! Thank you for watching and I have several others that you might enjoy!

The only way to charge a system with liquid through the high side is when the system has been completely recovered, and evacuated. Once you have pulled a good vacuum down to 500 µm you can put 100% liquid into the liquid line and you will see the pressure on the low side gauge go up. When the low side gauge comes up and it is basically, the same as the high side and you do not feel any refrigerant going in on the yellow hose which is the center hose then you can close off the high side valve and start the unit up. You will need to complete charging the system, but you will get most of the refrigerant. You need into the system this way. I hope this answers your question. And thank you for watching!

@@AirConAcademy thank you for the reply .... if the system is off , won't the liquid ref harm the compressor ?

@@SahilSingh-m9m good question, I have had other people/students asked me this. But if we think about it. We are putting all of that liquid in the liquid line. And between the liquid line and the compressor you have the condenser and that holds a lot of refrigerant. On the other side of the liquid line, we have the metering device/metering device will create a pressure drop and go into the evaporator so we really don't have to worry about liquid getting back to the compressor that way either. just so you know, I have been doing air conditioning since 1979 and I have done this countless times and never had a problem. The only problem you have is when you put liquid into the suction line without throttling it. When you do that it could get to the compressor. I hope this makes sense. And again, thank you for watching!

@@AirConAcademy thank you very much for the clarification 😎

@@SahilSingh-m9m I am glad I could help! And thank you for watching. If you get a chance, check out my other videos. A lot of guys have said that they have learned a lot through my videos on my channel. Aircon Academy. good luck out there! And be safe!

That, is a good question. at the bottom of the accumulator there's that orifice that keeps pulling the liquid refrigerant from the bottom into the system and it atomizes it due to the ventury affect so that we always keep liquid refrigerant going back to the compressor when it is atomized the compressor, compresses it and keeps the system going. I hope this answers your question. That was a good question! Thank you for sending that in and thank you for watching!

Wow! Thank you so much for your kind words! I'm glad you liked the video and if you get a chance, look at my other videos I have several videos on the refrigeration cycle, heat pump cycle and different components. If you just go to my KZbin channel aircon Academy you might find other videos that might help you. Thank you for watching!

Thank you very much for your kind words! I'm glad you liked the video and thank you for watching!

Yes, there are other colors. I have also seen purple out there. But here I was just pointing out a specific type. I guess I could make another video where I point out to her colors? But thank you for your comment and thank you for watching!

WOW!!! very good!!! I try to explain that in classes thank you on large motors we need to keep track of this information to see if the motor is failing. I believe most of the time once it is explained the guys in class understand why it is important. to me that is important getting them in class to understand why we do these things. thank you and thank you for watching!!!

Thank you so much!!!! The TXV is controlling the refrigerant going in to the evaporator, this is controlling the refrigerant going in to the compressor so you can adjust the capacity of the unit or the compressor. so you can turn the unit in to a 10 ton in stead of a 15 ton and back in to a 15 in case you need more cooling. I hope this answers your question? and Thank you so much for the kind words. thank you for watching.

@AirConAcademy we can control the cooling by txv adjustment if it's electronically controlled txv based on temp, so by unloading the compressor also we're reducing the cooling performance, right? Only difference is if we reduce compressor load , energy is saved extra , right????

@@bt9604 by adjusting the TXV, even if you are using an electronically controlled TXV, you are only adjusting the super heat in the evaporator. You are not adjusting the room temperature. A lot of times when you have an electronic expansion valve. The compressor is going to be an inverter unit, meaning that as the electronic expansion valve adjust or let's say closes the comp is going to slow down also. So it is not just a matter of adjusting the expansion valve. We have to worry about what the compressor is doing also. The unloader is actually going to adjust capacity of the compressor to meet the load demand. So it will turn a 30 ton compressor into only a 20 ton compressor, or maybe even a compressor depending on the application. if you do not adjust the speed of the compressor and you close the TX some your evaporator temperature will drop and it could freeze the coil because compressor speed was not adjusted. Hopefully this explains your question?

@AirConAcademy thanks🫡

Thank you! Yes, they are so they can control the capacity of the systems. some of the guys I have met have never seen unloaders. That seems to give them an understanding as to how they work. Thank you, and thank you for watching!

If I understand you correctly, yes, you should be able to do the pump down at the king valve. But you say you have two king valves? Just so that I understand you correctly one king valve as you call it is on the liquid line which is going to be sending refrigerant to the eight units, and the other king valve is that on the suction line? I'm not sure why you would have to valves unless you have a valve on the suction and one on the liquid line? For your gauges, yes, you would hook up the blue to the larger line, which is the suction line. And I will give you the pressure on the low side of the system. This was one of the reasons I was wondering about the two valves that you called king valves? I think you are referring to the suction line service valve into liquid line valve. You could call the one on the liquid line king valve. I have some videos on here that talk about pumping the system down. I don't know if those would help? Please let me know if this answers your question or if you have any other questions. Good luck and thank you for watching.

I'm glad you liked the video! And thank you for watching!

Thank you! Thank you for watching! I'm glad you liked the video!

Thank you for the suggestion!!! I am making a note of it and I will see what I can do! Thank you so much for your suggestion!

Thank you so much for your kind words! I am so glad to hear that I have helped you learn! I will make a note of it and try to do my best to make a video. I have just been so busy teaching! And thank you for watching!

Thank you! Yes, it has been a while, I have been busy teaching so much. I hope to have some free time first of the year. Thank you and thank you for watching!

CHAD!?!?!!! WOW!!!

Thank you, I'm glad you like the video. And yes, it has been. I have been so busy teaching. I hope to have more free time and yes, I will make a note to make a video on inverter technology. Thank you and thank you for watching!

I am glad that I red deer message and that I could help! I'm glad you liked the video! And Thank you for watching!

Thank you so much! I appreciate that and thank you for watching!

Thank you! I'm glad you liked the video and thank you for watching!

Thank you! I'm so glad to hear that. That's why I make these videos, I want to help you guys out there! I'm glad you liked the video and thank you for watching!

On heat pumps, it is a matter of time and temperature. So it is every 30, 60, or 90 minutes that it will check to see if it needs to go into defrost. The way it knows if it needs to go into defrost is because of the defrost thermostat, this is where the temperature comes in. The defrost thermostat is not closed because the temperature of the coil is so cold then it will just keep running in the heating mode. So when both time and temperature are calling for it, then it will go into defrost for, no longer than 10 minutes. If things are working properly and the charge is correct then the heat pump should come out of defrost within three minutes. This is how the defrost works, again because of time and temperature. I hope this answer answered your question, thank you for watching.

Thank you! I'm glad you like the video and thank you for watching!

Thank you very much! I'm glad you liked it and thank you for watching!

The reason you need a manifold set or gauges to pump down is because you need to see what the pressure is on the low side. And you only want to run the compressor as you are pumping down down to zero pressure. Because if you go into a deep vacuum, you may ruin the compressor.

You ask about Maritime? I learned a lot of this in the US Navy. We had chillers refrigeration equipment and all kinds of equipment that ran off of seawater to cool the condenser. Where are you located? Where do you work?

It could have been that it was low on Freon. But it should only be in defrost for 10 minutes maximum. So having the pressure and the discharge like that should not affect it that much. It is odd that at 46°. It went into defrost. You could also have a bad defrost thermostat and if it failed in the close position, which they do sometimes, then no matter what the outdoor temperature is it will still go into defrost. So make sure you check that defrost thermostat operation. And thank you for your kind words! I hope this helps and thank you for watching.

Thank you and thank you for watching!

No, I don't believe I have any questions videos about headmaster valves. I have videos about EPR evaporator pressure, regulating valves and compressor crank case pressure regulating valves. Maybe I will make a video on that. Thank you for letting me know and thank you for watching.

That can easily be done by first closing off the king valve, which is the valve on or right after the receiver, then you would close the suction service valve, that should be before the accumulator. When you push the contactor in to make the compressor run, you would boil the liquid out of the accumulator and into the receiver. once you have done this, you can close off the liquid line service valve on the liquid line, which is before the receiver and refrigerant should have gone into the receiver. I hope this helps! It is called a pump down procedure. Thank you for watching and sending your question in!

@@AirConAcademy thank you 🙏🏾 what kind of pump would pump the liquid refrigerant from the accumulator back to the receiver is the compressor slugging

Other than pumping it down, using the pump down procedure, the only way to get it to move around, would be the recovery machine. The recovery machine could be used as a pump to move it from one place to the other. typically it is a pump down procedure. I hope this answers your question. Let me know.

@@AirConAcademy thanks i think pump down or evacuating the system with a vacuum pump will be the way to go thank you again

@@tyhamell5425 be careful because when you use a vacuum pump, that would not be the correct answer. The vacuum pump would pump whatever is in there to the atmosphere. With a recovery machine, you could move it from wherever over to the receiver. But the correct thing to do would be to pump the system down. So you pump everything onto the high side, including the condenser and the receiver. Whatever is in the accumulator or the evaporator pumped into the condenser and into the receiver...

Thank you! I am glad you like it. I like to simplify things because I know how difficult it was for me. Thank you for watching!

Thank you so much! And thank you for watching!

I am sorry to say that one of the things that changes is the size of the orifice. So it will be necessary to change the entire metering device/TXV I wish it was that easy, but the whole thing should be replaced. Thank you for watching!

Hi! Yes! As you can see in the video, I am boiling water at 70°F! To do this you lower the pressure in the vessel and as it absorbs heat from the surrounding area, it boils. I don't know where you are, but if you are in an area that is approximately at sea level water boil at 212°F. You are up in the mountains. The water will boil at a lower temperature. If you are approximately 5000 feet above sea level water will boil at 203° because the pressure is lower. This is how the refrigeration cycle works. The metering device will lower the pressure and because of that we can have refrigerant boiling at approximately 40°F. because the compressor compresses the refrigerant and the pressure we can make the refrigerant from vapor to liquid, in other words, we can get it at a temperature of approximately 120°F, Fahrenheit, Fahrenheit. So to answer your question yes we make water boil by lowering the pressure. Thank you for sending your question in, and thank you for watching!

The only explanation that I have is that when you pull down to 500 µm the boiling temperature of water drops down to 0°F. so if you are working on a unit and it is 35 or 40° outside by pulling down to 500 µm and it holds, you are sure to remove all of the moisture from the system. the lower you bring the pressure the lower the boiling temperature is. Keep in mind that because the new refrigerants are using POE oil, the oil will not release the moisture. So we need to make sure that we get as much of it out of their as possible. I hope this answers your question. And thank you for watching!

​@@AirConAcademythankyou 🙏 now i understand.

Thank you so much for your kind words! And thank you for watching!

This really only works for the reciprocating compressor, which has the suction and discharge valves. On a rotary compressor there are no valves. It draws the refrigerant in from one side and acid rotates a compress it and pushes it out on the other side. So you really do not have suction and discharge valves, like you do have on the reciprocating compressor. I hope this answers your question. And thank you for watching!

Thank you so much! And thank you for watching!

I am glad you liked the video. And thank you for watching!

Ha ha ha! Yes! That will usually show you where the problem is. It is one of those one way troubleshooting ways and sometimes there is no coming back from there lol thanks a lot that was great! And thank you for watching!

The two valves you are talking about are they suction service valve and the discharge service valve. Those valves need to be opened all the way to where it is called back seated. When they are all the way to the back, you will not have access, or you will not be able to read precious when you hook up gauges. If you want to pressures at the compressor then, they should be with the mid position or cracked. That means that they are off of the backseat. If you close the valves completely, then they are considered front seated, and the compressor will not run because there will be no flow of refrigerant through it. Those pressures are giving me seem to be pretty close. Do you have a site glass anywhere on the liquid line or on the receiver/dryer? Do you want to make sure you have enough subcooling and with the bus running a different speed your pressures are going to change. As the bus speeds up the engine wraps up, which is going to turn that compressor faster and change your pressures. So you need to make sure you have sub cooling coming out of the condenser. Usually there's a site glass somewhere so you can make sure you have a full color of liquid going to the metering device. I hope this answers your question. Good luck and thank you for watching!

@@AirConAcademy awesome man! I really appreciate you explaining this to me because this compressor is totally different from a regular little automobile compressor being that this '05g has six Pistons I will make a video of the RPMs of it running and show you the gauge pressures. I noticed the high pressure gauge was bouncing?

@@SMOKEY-JAYS-DIESEL great! If you do that, I would love to see it! You can send it to me to my email address. [email protected]

The unloaders on some manufacturers are energized for them to be loaded and on others they have to be de-energized, or another words no power going to them for them to be loaded and doing work. Depending on the age of the unit like an older units, they could be controlled through the thermostat. Then they were controlled through a Honeywell controller and these days they're controlled through circuit boards or computers that control the building temperature. I would start by looking at the schematic and see where the wires go to from the unloaders that are on the compressor. By tracing them back, you can see what is turning them on and off. I wish I could give you more information, but if they're not loading at the moment, you could check to see if they have voltage going to the unloader if they do, you can undo the voltage wires in that should load it up. And you could run it temporarily until you figure out how they are being turned on and off. Hope this helps! Thank you for watching. If you have any other questions, please shoot them my way!

Thank you! I'm glad I could do that and thank you so much for watching!

Thank you! I'm glad you like the video and I hope that it helps you out there! Thank you for watching!

Very helpful like me I'm a newbie about chiller

@@sadikthebasicmaster4689 don't feel bad! We have to start somewhere and the more you do this the more you research the more you will know! And like a tell everyone in class the more you know the more valuable and the more money you can make! So keep learning! And again! Thank you for watching!

@AirConAcademy you're welcome sir