The Engineering Mindset for a 15KW (with PHE) Capacity System , We used TE12 - Orifice 6 ( We didn't consider the Sub-Cooling caused by PHE + we weren't using PHE initially) Effectively System was delivering 10kw ODU with 15KW idu with TE 12 Orifice 6. @ 8psi Suction & 275psig Discharge. 1 system later failed as 2 cyclinders of compressor discharge reed went off, as soon as we enabled PHE,( may be or bcoz of TXV) Question is was the failure because of TE12 during normal Operation or the mismatch of PHE & TXV. Accurate Txv is TE5 Orifice 3. for the system (later as we considered additional Sub-Cooling)?
This channel is amazing, the detail that goes into your animations as you describe these processes is a true gem of a study aid, I am a studying hvac apprentice and I'll be using this material to get this stuff down cold!
This is a wonderful exploration a relatively complicated subject. I am currently replacing a compressor and txv for a home owner. This is a fantastic video to share with him while I complete the repair. Thank you .
Change of state begins the moment the refrigerant passes through the tx, not just at the end of the evaporator. There is one constant temperature for as long as the refrigerant is changing from liquid to gas.
Thank you so much watching this video. I Now understand Automotive type of expansion valve. Although it's very different it's also very similar. The automotive one does not have the capillary tube. It has a high pressure line and low pressure on the same block.
Great discussion on the function of the bulb...its pretty clear that if the valve gets stuck in the closed position, there will be no cooling even though the refrigerant in the bulb is expanding against the diaphragm (trying to open the valve).
Very nice explanation of simple TXV. But would be nice to have quick overview of some variants, like what is the third port on TXV which connects directly to the suction line?
It's the external equalizer line. Big evaporators need externally equalized TXVs because pressure drops considerably inside them, so the equalizing pressure is sourced from the evaporator's outlet rather than from the TXV's outlet.
Quick question: when you say the expansion valve will open more, you mean there will be more vapor in the flow (higher x value) or less ? If you cooling load is high (low x value), then the temperature after expansion, as well as after evaporation are high. In order to decrease the temperature after evaporator, you should decrease the temperature after expansion, this means you need have flow with high vapor fraction after expansion. Combining this logic and your description, the more expansion valve open indicates more vapor fraction in the flow. Am I right?
Can you please explain in temperature vs entropy diagram that how there is no entropy change in process 1-2 even when compressor compresses refrigerant? I believe that entropy should increase if any gas is compressed.
Not sure if you care to know, but around the 2:10 mark, you show a recording of a sensing bulb strapped to the suction line and it’s strapped with two zip ties Obviously it’s still going to sense the temperature off the suction line, but you should use a metal clamp instead because that metal clamp helps distribute the “coldness”-for lack of a better term-evenly around the sensing bulb and not just on the mating surfaces. Not trying to be a know it all. I just assume you like to constantly get new relevant info. Thanks Paul! I’ve almost watched all of your videos
Great explanation of THX with excellent illustrations. But please make the music lower then the narration so that the backround does not dominate speaking.
Super! Fantastic educational explanation. Please add few words about TXV capacity VS system capacity, means to say can it be variable or must be same as system capacity. Thanks
So basically a higher temperature at the other side of the evaporative coil opens the valve and a cooler temperature closes it. The goal is to keep the refrigerant a gas for the compressor to compress (liquids don't compress) and to keep the system from freezing in an ac unit. So in adjusting tightening the spring lets less refrigerant in thus increasing exit temperature and loosening decreases exit temperature.
Working on a 404a commercial freezer. Thing was at 96 degrees Fahrenheit when I arrived. Compressor was hot. Low pressure was in a vacuum. Would the TEV cause this being that it’s stuck and the pin is restricting flow?
My sensing bulb broke and there was black stuff in it and the compressor turned off and I can get it to come back on how would I fix it or even rig it for now
Good day Sir. I just want to ask something. I have an upright freezer that I wanted to make the freezing faster. Can I use the TXV, to modify the speed of running refregerant. Thanks in advance for any info.
This works like any capillary tub temperature switch as the bulb warms pressure rises this works great on things like pressure washers that also heat the water this way we can read the temps of the pipe but also not have to actually break into the high pressure line
@@EngineeringMindset In automotive H-block type expansion valves the bulb is located inside the suction line connector (the plasticy looking cylinder that you see inside one of the holes on the compressor side of the expansion block).
may i ask if there is any relief valve to absorv excess liquid in case txv failed? this way we can reduce or protect the compressor to be damaged as you said because of gas failed to change phase to vapor?since liquid is incompressible and will stall the pump and eventually damage associated parts.
I believe TXVs are designed to close by spring pressure during failure but they don't close completely due to mechanical stop. I suppose it's possible for a TXV to get stuck wide open which might allow liquid back to compressor but probably rare.
I have a question. Is TXV only changing the liquid mass flowrate of the refrigerant through the TXV since the outlet is a mixture of liquid and vapor, or the total mass flowrate of the refrigerant? The reason that I am asking is that the total mass flowrate of the system should be constant. So the mass flowrate of the refrigerant entering and leaving the TXV should be the same in a closed system. If the TXV is changing the total mass flowrate, then where is all that refrigerant going coming out of the compressor (single speed compressor)?
⚠️ *Found this video super useful?* Buy Paul a coffee to say thanks: ☕
PayPal: www.paypal.me/TheEngineerinMindset
Its said , cap-ughh-larry. overall great video. A1
The Engineering Mindset for a 15KW (with PHE) Capacity System , We used TE12 - Orifice 6 ( We didn't consider the Sub-Cooling caused by PHE + we weren't using PHE initially)
Effectively System was delivering 10kw ODU with 15KW idu with TE 12 Orifice 6. @ 8psi Suction & 275psig Discharge.
1 system later failed as 2 cyclinders of compressor discharge reed went off, as soon as we enabled PHE,( may be or bcoz of TXV)
Question is was the failure because of TE12 during normal Operation or the mismatch of PHE & TXV.
Accurate Txv is TE5 Orifice 3. for the system (later as we considered additional Sub-Cooling)?
Is Thermostatic expansion valve principle the same with Direct Cooling Technology?
The Engineering Mindset what happened to your VRF videos? I can't find them
New VRF unit video here:➡️ th-cam.com/video/4i1XgcP1tmw/w-d-xo.html
This channel is amazing, the detail that goes into your animations as you describe these processes is a true gem of a study aid, I am a studying hvac apprentice and I'll be using this material to get this stuff down cold!
no pun intended??
How've you gotten on with the apprenticeship? Fully qualified now??
Recently got into the commercial refrigeration trade. Been watching your videos since I started. I appreciate all the info really helpful
I literally jumped when that compressor in animation, exploded 🤣
Same
same here lol
Same here
Smae
Hahaha me 2
I have watched videos from dedicated hvac techs and I was still confused. You explained it perfectly. Thank you
Got my SV Second Engineer oral exam next month and these videos are a godsend! Thank you!
Wow, absolutely high quality stuff. The level of details, clear narrative and even background music... Good job and tons of thanks!
This is a wonderful exploration a relatively complicated subject. I am currently replacing a compressor and txv for a home owner. This is a fantastic video to share with him while I complete the repair. Thank you .
nice. i was dozing off near the end of the vid....suddenly "BOOM"... good one!
Haha! Me too.
Exactly lol
That got me😂
Same here! Lol 😂
Lmao same here
Great simple video explaining the process for someone who is not an HVAC tech. Thanks.
This is the best one on AC systems. Thank you !
This is the best video I’ve seen explaining the TXV. Thank you 👍🏼
Very well explained and highly informative.
Compressor damage/ explosion due to liquid entry is worth the highlight.
Organized and detailed explanation, i like the analogy and circled appointed equipment when the narrator speaks
Change of state begins the moment the refrigerant passes through the tx, not just at the end of the evaporator. There is one constant temperature for as long as the refrigerant is changing from liquid to gas.
This is a great video for understanding the importance of TXV and its working principle.
These are the best videos I've seen on TH-cam. 👍 Thanks
This simplified so that anyone can understand thank you
I went from 😴 to 👀 when compressor exploded. Well animated video, for those new hvac techs 👍
That Jump Scare Explosion.
I thought I was the only one XD
I use a Denon amp for my pc.
I almost threw my mouse across the room!
Thank you so much watching this video. I Now understand Automotive type of expansion valve. Although it's very different it's also very similar. The automotive one does not have the capillary tube. It has a high pressure line and low pressure on the same block.
Yes, we have a video on EEV also please check our page
Turn up the volume when you're recording your videos thanks man. Thanks for the video
Lol
Well said you really summed up the entire information from the beginning of your video in your example. Thank you.
Thank you very much.You made a very clear explanation about refrigeration system
Great discussion on the function of the bulb...its pretty clear that if the valve gets stuck in the closed position, there will be no cooling even though the refrigerant in the bulb is expanding against the diaphragm (trying to open the valve).
Finally, got it, thanks for sharing!
this guy is an amazing teacher 😇😎🤓
Very nice explanation of simple TXV. But would be nice to have quick overview of some variants, like what is the third port on TXV which connects directly to the suction line?
It's the external equalizer line. Big evaporators need externally equalized TXVs because pressure drops considerably inside them, so the equalizing pressure is sourced from the evaporator's outlet rather than from the TXV's outlet.
Had watched this once before, forgot the thumbs up; got it right this time around.
Marvelous explanation.. no more word to say
Quick question: when you say the expansion valve will open more, you mean there will be more vapor in the flow (higher x value) or less ? If you cooling load is high (low x value), then the temperature after expansion, as well as after evaporation are high. In order to decrease the temperature after evaporator, you should decrease the temperature after expansion, this means you need have flow with high vapor fraction after expansion. Combining this logic and your description, the more expansion valve open indicates more vapor fraction in the flow. Am I right?
Perfect explanation 👌 👏 👍
Compressor spontaneous disassembly was a good chuckle, thank you. :D
Ευχαριστούμε!
Thank you!
That explosion almost knocked me out of my chair haha.
excellent graphics and good explainations
Great Geat video !! Helped me a lot !
nice always wondered what they did thanks for sharing
Good explanation of the system. Thanks
Thank you for this very understanding information.
Excellent video!!
Thanks in a million. Great content. Awesome. Grade: A++💥
Great video as always.
Superb explanation. Thanks
Thank you so much 💓 for this inriched informative video
Can you please explain in temperature vs entropy diagram that how there is no entropy change in process 1-2 even when compressor compresses refrigerant? I believe that entropy should increase if any gas is compressed.
Great video , thanks 👍
Not sure if you care to know, but around the 2:10 mark, you show a recording of a sensing bulb strapped to the suction line and it’s strapped with two zip ties
Obviously it’s still going to sense the temperature off the suction line, but you should use a metal clamp instead because that metal clamp helps distribute the “coldness”-for lack of a better term-evenly around the sensing bulb and not just on the mating surfaces.
Not trying to be a know it all. I just assume you like to constantly get new relevant info. Thanks Paul! I’ve almost watched all of your videos
Thanks Josh, nice tip.
Who the hell thumbs down solid material such as this!? People take time to make such videos that help thousands and you get such d***s out there 😒
Great explanation of THX with excellent illustrations. But please make the music lower then the narration so that the backround does not dominate speaking.
Very Educative. Thanks
Awesome video! Thank you!
I learned so much.thank you sir.
Superb! Very helpful for people like me who are venturing out into this field:
ie- Marine engineering.
Will you please do one on steering system
Super! Fantastic educational explanation. Please add few words about TXV capacity VS system capacity, means to say can it be variable or must be same as system capacity. Thanks
Could you please explain about the equalising line? Why is it required? How it works?
He just told you
Thanxs more we follow ur video always from Iraq
lovely videos...keep ur efforts continued.
So basically a higher temperature at the other side of the evaporative coil opens the valve and a cooler temperature closes it. The goal is to keep the refrigerant a gas for the compressor to compress (liquids don't compress) and to keep the system from freezing in an ac unit. So in adjusting tightening the spring lets less refrigerant in thus increasing exit temperature and loosening decreases exit temperature.
So is that why you check sub cooling with a TXV system? Im new to this , trying to learn.
Very helpful, thank you very much
Nice explanation.
7:42 scared the Bejeebers out of me.
Working on a 404a commercial freezer. Thing was at 96 degrees Fahrenheit when I arrived. Compressor was hot. Low pressure was in a vacuum. Would the TEV cause this being that it’s stuck and the pin is restricting flow?
How is indoor TXV bypassed in heat mode? does bulb simply open it all the way and size of the line matches size of TXV opening?
Why the capillary tube is coiled at the top of the valve? Is it just to add buffer length or does it have some function?
My sensing bulb broke and there was black stuff in it and the compressor turned off and I can get it to come back on how would I fix it or even rig it for now
Amazing explanation
...thanks
Great Video!
Best explanation! Very quality picture!)
Very good info.
This is great. Thanks for your educational videos. Alot of thanks.
I was waiting for you to tell us how to know if the super heat setting is right or wrong and why and what to do about it.
Awesome explanation . Thanks a lot 😊👍🏻
Excellent video, Is it possible to close TXV completely to stop the liquid refrigerant flow to the compressor when the load on equipment is very low.
What happens when you flip the unit into reverse / heating? What does the TX valve do then?
Good explanation
Question the inlet/outlet of the TXV...is it inlet from the condenser and outlet to the evaporator
Yes, but always check the manufacturers notes for the model you're installing
I just love your videos, man! Thanks!
what happens with the pressure inside the evaporator when more liquid is injected? thank you nice videos
Does the TXV have to be installed close to the evaporator inside the cool room or can it be installed on the outside of the cool room? Does it matter?
Good day Sir. I just want to ask something. I have an upright freezer that I wanted to make the freezing faster. Can I use the TXV, to modify the speed of running refregerant. Thanks in advance for any info.
very good👍👍👍👍
A very well understanding,thank u
Is the sensing bulb completely separate from the loop? Or does it tap into it and share the same liqiuid
Separate
This works like any capillary tub temperature switch as the bulb warms pressure rises this works great on things like pressure washers that also heat the water this way we can read the temps of the pipe but also not have to actually break into the high pressure line
@@EngineeringMindset In automotive H-block type expansion valves the bulb is located inside the suction line connector (the plasticy looking cylinder that you see inside one of the holes on the compressor side of the expansion block).
What part in the refrigeration system that is directly responsible in regulating evaporator temperature?
may i ask if there is any relief valve to absorv excess liquid in case txv failed? this way we can reduce or protect the compressor to be damaged as you said because of gas failed to change phase to vapor?since liquid is incompressible and will stall the pump and eventually damage associated parts.
I believe TXVs are designed to close by spring pressure during failure but they don't close completely due to mechanical stop. I suppose it's possible for a TXV to get stuck wide open which might allow liquid back to compressor but probably rare.
What happens if the capillary tube breaks off the txv? Does that make the clutch on the compressor kick on or off?
This is intimidating knowledge. Is this a necessity when getting started with installs?
I have a question. Is TXV only changing the liquid mass flowrate of the refrigerant through the TXV since the outlet is a mixture of liquid and vapor, or the total mass flowrate of the refrigerant? The reason that I am asking is that the total mass flowrate of the system should be constant. So the mass flowrate of the refrigerant entering and leaving the TXV should be the same in a closed system. If the TXV is changing the total mass flowrate, then where is all that refrigerant going coming out of the compressor (single speed compressor)?
Did you mention the function of sensing bulb?
Excellent video. Keep it up.
Awesome vid!
Thank you 🙏
Nice video.. Thanks
Marvelous explained but back sounds little bit irritating. Keep up good work
Could you please tell me sensing valve filled by which fluid?
How does the refrigerant get into the sensing bulb?
In some designs we have a feedback acting from downwards! Please include the explanation for the same
WOW good teaching for me..