Chiller - Expansion Valve HVAC

[@EngineeringMindset]

⚠️ *Found this video super useful?* Buy Paul a coffee to say thanks: ☕ PayPal: www.paypal.me/TheEngineerinMindset

[@shaikhsalman1509]

Hey Mate...I am a HVAC engineer and over a period of 6momths I keep watching your videos and confidently say no one gives explanation on HVAC better then you...God Bless you and may give you lots of success ahead...

[@moviefreak4672]

Hello. I'm also an HVAC Engineer. Is there any more youtube channel you follow for learning? Can you suggest me please?

[@unclemonster48]

These videos are really good! Thank you for educating the masses! The mcquay machine your displaying the bulb from the pilot valve goes to a well on the top center evap. There is a temp sensor that is mounted on the suction 90 that gives the suction temp. to the microtech controller. The pilot valve is controlled from that bulb that is mounted in the evaporator. But all in all your videos are fantastic for getting guys familiar with chillers and also us seasoned guys for a little refreshing. Especially when all I’ve been doing is rebuilds.

[@josephdailey9695]

This is a great channel and so glad I came across it. Thanks and keep up this great stuff/

[@saeedhameed9148]

thanks for making these videos full of information and knowledge

[@hvacguy11]

Dude your videos are the best out there for HVAC industrial stuff no one has this type of explanation like this I highly recommend subscribing with the bell on lol

[@EngineeringMindset]

Thanks, glad you enjoy them and its helping

[@RaceForGoodLife]

class on my phone! awesome channel! thank you I watch them all thanks!

[@deepraja]

Excellent job , Paul. Please keep it up. Your coffee is on its way !!. Thanks once again

[@nyimachoenyi4997]

Great video !! Thumps up.

[@ronakgothi9406]

Thanks for this video....its really helpful.

[@sharbekmm]

the best explanations really thanks

[@hoangvd7994]

Thanks for your really great and helpful video, and can you advise what is a differences between Internal and External Equalizer Thermal Expansion Valve. Thanks

[@EngineeringMindset]

An internally equalized TXV uses evaporator inlet pressure to create the ‘closing’ force on the valve. An externally equalized valve uses the evaporator outlet pressure, thereby compensating for any pressure drop through the evaporator

[@RahulGawade123]

This is nice video. Can you tell us how capillary tubes work as expansion device? I saw it in various Water coolers.

[@yuvarajc8951]

Sir u r done great job........this video more useful to me so keep doing in Chiller video

[@muhammadabusayed3136]

thanks for such video. it clear my view

[@mr.zenoh.2560]

Thank you

[@kisyanto907]

Good and very experience

[@cikgurandom5850]

thank you so much. great explaination

[@atumbijally3079]

Thanks for the explanation 👍

[@muhammadawais6336]

perfect my friend and thanks

[@RP-nc5ev]

Thanks

[@janicesmyth2183]

thank you so much for your videos!

[@nikkuthomasabraham3784]

Well explained.

[@movax20h]

The pilot expansion valve is like Darlington transitor pair in electronics.

[@gregorymalchuk272]

I have a question. As the load decreases and the superheat decreases, what happens to the liquid refrigerant in the line between the pilot valve and the main valve that enables the main valve to close? Does it leak back through the pilot valve, or is their a bleed at the main valve that allows pressure to leak down? Thanks.

[@majedal-harbi1774]

Thanks A lot

[@ibrahimosman3393]

Very useful

[@gonzalomunoz]

Excelentes videos, una genial explicacion

[@mohammedimran6328]

Thanks for your very helpful video and i am very grateful for your work. I have a question, If the expansion controlled flow of refrigerant then why IGV inlet guide vanes are used in centrifugal chiller? I hope you will clear my doubts.

[@EngineeringMindset]

We've covered this in our series, can watch it here kzbin.info/www/bejne/nF6xZZypnLaFfbM

[@ShimoDarkhani]

Hi Sir, Can you help me out, that how can get recover the Oil in Sump from Evaporator in Centrifugal chillers.?

[@ShimoDarkhani]

Hi Sir, Can you help me out, that how can get recover the Oil in Sump from Evaporator in Centrifugal chillers.?❤

[@holmanyusedciprianoliveros8935]

Hi, I appreciate you help me with this doubt, The expansion valve decreases temperature and pressure because it increases the flow area or because it places a restriction for its passage, preserving after this restriction the same flow area?

[@EngineeringMindset]

It creates a build up of pressure on one side and then the small opening causes the refrigerant to suddenly expand. Its like holding your thumb over a hose pipe

[@kasimshaikh3750]

@@EngineeringMindset but how does that reduce the temperature to 6-7 °C.When it's around 26-30°C in the condenser.

[@neelpunghera2639]

@@EngineeringMindset sir I've a same question too. Currently I am working on it as research base and I really wonder how does it happen to drop the temperature from 24-25°c to 9-11°c just after expansion valve? I mean yes expansion valve will drop the pressure and so the temperature but this much and sometime it's feel like magic happened there😅..! How? Please guide me.

[@heshwanth]

Where does the refrigerant gas goes from the pilot expansion valve once it pushes the main expansion valve. How does it recoil? Can someone explain me

[@mechanical-g8w]

tanx

[@holmanyusedciprianoliveros8935]

Another questions. What happens if the day is cold, from the controller can I raise the cold generation range, other than 6 ° C but 10 ° C? This directly affects the flow of refrigerant that will allow the passage to the expansion valve by means of the thermal valve that is in the suction line towards the compressor, is it correct? How can I calculate how much coolant is required to cool a degree of temperature

[@EngineeringMindset]

Most chillers will allow you to vary the set points but do make sure you are authorized and competent to do so first. increasing the temperature will result in energy savings, 10 is a little high, 8*c would be more common. Can do refrigeration calcs in the video kzbin.info/www/bejne/ioHEk6lvnql4hMU

[@pawanYadav-zi6bz]

great

[@muhibali205]

Great

[@IceyJunior]

Nice

[@scottvanruin6481]

Why can air compressors deal with liquid when the compress air in the piston cavity but not refrigeration compressors, negating the fact for refrigeration liquid dilutes the oil?

[@DeepakRohra]

Thank you so much for the explanation :) i just had one question, The refrigeration cycle starts with the suction stroke of compressor right ? if yes then in that case how does the flow of refrigerant takes place ? i mean does the evaporator is filled with the refrigerant ?? thanks again

[@EngineeringMindset]

Hello, yes refrigerant sits around the machine when idle, it only moves when the compressor starts. Over time the temperature will begin to equal out but as the machine starts it will change again.

[@rccanuck4473]

What would cause the evaporator pressure to drop too low ?

[@EngineeringMindset]

There's a lot of reasons it might happen. Possibly a tube blockage, too high water flow rate, maybe the wrong delta T from design. Have a look on the BMS logs to see what was occurring at the time of fault. Compare it to other times and see if there is a comparison. If it gives an error code then look it up with the manufacturer to diagnose.

[@EngineeringMindset]

We just covered chiller faults in our recent video! kzbin.info/www/bejne/kKaTfYmMg7OJidk

[@cagriceylan1491]

the VRF link does not work, can you fix it? Thanks in advance.

[@EngineeringMindset]

New VRF unit video here:➡️ kzbin.info/www/bejne/apqUiZqZhZano9k

[@JoaoSousa-x4r]

Can you share the 3d models

[@benardasiimwe4414]

Hello engineering mind.com Am Benard currently working in Qatar ,I have a question Do u have HVAC school in Qatar

[@EngineeringMindset]

No, we only have our website no physical schools

[@engineeringmaniac9696]

The difference between Engineering Mindset and other channels is that this guy steps down to a kids level to explain things and makes it super cool to learn. Love your works. You really shaped my interests.

[@TheAkshay09]

hey mate, I've been watching these videos actively since starting in building services this year and just wanted to say how well you've explained the content so thanks very much. Some suggestions for potential topics that could be covered for future videos: Absorption chillers, co-gen/tri-gen systems, HVAC technical drawings, maybe even one on how the building services industry works ie. contractors, sub-contractors, consultants, service technicians. Thanks again!

[@EngineeringMindset]

Great suggestions, I'll add them to the list.

[@EngineeringMindset]

Absorption Chiller video is now live! kzbin.info/www/bejne/ZoObZZuCpdeCa9U

[@holmanyusedciprianoliveros8935]

tri-generation systems would be great, please please take this topic, thanks.

[@Valentinaobumnaeke]

Why is my expansion valve opening full

[@MrGreatcons]

Thank you man you are very helpful 😍

[@EngineeringMindset]

Learn *CHILLER COOLING CAPACITY* here: kzbin.info/www/bejne/eIvbiXyarbt-m7s

[@jangradev]

Hello, sir... Please make a vedio on.. Scaling of condensor evaporator in chillers, Also best method and tools require for maintenance of water cooled chillers.. Thanks for ur all vedio, Ur vedio so help full for me and others.. Sir we don't have much money to get tools Sir, superheat in chiller, I can't understand How to implement superheat data on small Ac for solving cooling problems... Again thanks for ur valuable vedios...

[@mikefochtman7164]

Nice video but you don't go into the aspect of the TXV sensing superheat. You mentioned the Thermal Expansion valve shown had an external pressure 'equalizing' line, but didn't go any further. By sensing both the compressor suction PRESSURE and TEMPERATURE, the TXV can actually sense the degree of superheat above saturation. The spring setting can determine the degree of superheat. So a drop in suction pressure will tend to open the valve, even if the suction temperature remains steady and vice versa. If the valve only responds to suction TEMPERATURE, then an overcharged system can still pass liquid into the compressor under the wrong conditions.

[@Bhajankerasik]

We are experiencing a problem in our chiller system which is having an electronic controllled expansion valve. We have charged the system with 20 kg of R407 gas after having an alarm of low pressure. But it was not rectified and pumping down the system..we could barely see any gas coming back to condenser which was showing 75% when we charged it earlier. What all we have checked is 1. Dryer....ok 2. Evaporater...ok no leakage 3. Expansion valve changed from a already working chiller system. Please guide us on what could be the possible cause of the syatem showing low pressure.

[@dm7m7]

Thank you for the information. I have a question, what do you mean by superheat? I bit you mean a superheated vapor. the thermal bulb which is located inside the suction line will sense the superheated vapor, but what I know is the status of the refrigerant after leaving the evaporator will be as a saturated liquid.

[@arturzych138]

I think it's so cool that it's a totally mechanical system, no electronics (unless you have the EXV). Making it a robust the system. Awesome, kudos to the engineers that developed these systems.

[@SlickManChoux]

Thank's 4 sharing. Appreciate.

[@rodrigoalonsoparravicini937]

Good video!! very clear, simple and with real examples, the key to learn any concepts in engineering !

[@nyimachoenyi4997]

Paul, can you please do a video about latest York air cooled chiller ?

[@JohnDowelll]

Recently started in the HVAC engineering industry and I love these vids!

[@shiwanlin]

Latent heat overheat

[@recardoromero6296]

Very nice thanks...❤

[@AllAroundHnadyMan]

Excellent education

[@IceyJunior]

how can liquid refrigerant flow to the bottom of the evaporator? it's it being pulled by gravity?

[@EngineeringMindset]

It's being pushed by the pressure generated by the compressor as well as the suction from the compressor

[@aissabousekri7665]

thank you very much sir .if you can tell us the most problems come on chiller ,and if you can explain litll a screw chiller

[@EngineeringMindset]

You might liek this video on chiller faults kzbin.info/www/bejne/kKaTfYmMg7OJidk

[@Samara200M]

Mindset be is good channel for show about electrical and electronic knowledge

[@surendermohansharma377]

Defind nicely

[@RP-nc5ev]

Great 👍 👌

[@surendermohansharma377]

Super

[@MR-nl8xr]

Bravo

[@shubhamraturi3348]

1. What will happen if water droplets get into a centrifugal compressor? 2. What will happen if gas or vapour get into a centrifugal pump? 3. What will happen if we remove expansion valve from the centrifugal chiller or vapor compression cycle? Thank you.

[@Sh-iv3zs]

Hello sir, I would like to tell you that the first chiller has a float or orifice plate and the small tx valve is used for motor/vfd cooling as the base of the orifice chamber has liquid in it. As this style evaporator is flooded superheat is definitely not used for refrigerant control as it is likely to only be 1k. We work on approach with flooded type evaporators. The 3rd chiller is a Trane RTHB it uses a exv than that feeds the economiser, this exv is positioned determined on discharge superheat, the liquid refrigerant in the economiser is then controlled into the evaporator through a orifice plate, the sub cooled vapour in the economiser is scavenged and recompressed. This style evaporator is also flooded. The later trane RTHC and D also had similar refrigerant cycles but the exv was positioned via a low side float and I believe they may be falling film type flooded evaporators.

[@A-GoldenBar]

Should bas control chiller staging using building btu or building chilled water supply temp. ?

[@rayyandeshmukh8255]

Thank you sir, Video was so usefull Sir, can you please upload any animated video how these vales works??

[@vineethrajagopalannair9514]

Hi can you upload the procedure for how to charge/Change refrigerant and oil to chillers? It will be of great help.

[@ahmadabulafi7493]

are you a mechanical engineer ?

[@EngineeringMindset]

See our new video on how to build mechanical versions of electronic circuits? Watch here: kzbin.info/www/bejne/kKecgmqfnZlri8U

[@sumeursault]

Enjoy your videos! From the novice perspective (me), I believe starting off with an explanation of the thermal expansion valve would have been a little easier since it's the simpler configuration

[@tomarankush]

One of the best videos I ever seen on KZbin regarding Hvac thank you so much

[@muneerhasan603]

Thank you for the Video!!! You’re the best

[@akashsadasivan6296]

Please explain about expansion tank

[@VinodKumar-gy7ft]

Nicely explained.

[@tonkie10]

Hi friend @theengineeringmindset I have a question for you, in another video I saw That in the sucction line there is a refrigerant low pressure, low temperature, saturated vapor, but why the thermal bulb is in the suction line?? because knowing that the discharge line has the superheated vapor it should be in the disacharge line because the compression isn´t happened yet. Tnank you in advance.

[@EngineeringMindset]

try this video it will help kzbin.info/www/bejne/pYSvgHt5hNxmr8k

[@hengchung1]

hi this is great video. Could you also explain the relationship between the temperature and pressure to control the expatiation valve. Thank you.

[@EngineeringMindset]

Check out of expansion valve videos

[@parvezalam7917]

what is the right superheat temperature for this kind of machine. I have 4 No's chiller which has different superheat

[@EngineeringMindset]

Hi Parvez. Have a look for the serial number and contact the manufacturer, they will give you the best advice as it will vary

[@fathmasameer7523]

Sir I am new on this field, thats why I am little confused about, so my question is why there is two valve, pilot and main

[@EngineeringMindset]

when the chiller gets too large, a normal TVX will not fit or work, so a pilot valve is used

[@kevinpansu]

chevere

[@mdumar7623]

What's is the temperature of refrigerant at 4 stages in chiller?

[@EngineeringMindset]

Details here: theengineeringmindset.com/water-cooled-chiller-design-data/

[@robthebuildermoore3331]

An expansion valve maintains a constant super heat across the evaporator.