Working of Expansion Valve , Defective expansion valve , Liquid return to compressor

How can you find a defective Expansion Valve on ship Fridge system??
How does an expansion valve Maintain Superheat temperature??
How do Thermostatic expansion Valves work??
When will you have a liquid Hammer in fridge??
Can liquid return to compressor if Expansion valve fails??
This video discusses about the working of Thermostatic Expansion Valve #TEV ,It discusses the importance of Superheat and also how to detect that Expansion Valve is Defective. Finally it discusses about the hazards of liquid returning to compressor. Pls see previous videos • How to understand the ...
and
• Refrigeration.Is Frost...
for better understanding
#Liquidhammer #Superheat
RMETC is a consultancy company for Marine Engineering Training specializing in conducted workshops on Hydraulic Failure Management Courses for various shipping companies, for thier international crew. More details at website rmetc.co.in

[@simioncsm5042]

Chief, very good job ! Your explanation is excellent! God bless you !

[@srinivasanthayyil4836]

Excellent presentation. Easy to understand with diagrams and animation.

[@rmetcvideos]

Thanks sir..endorsement from you means a lot to me...

[@shashanktantri]

Thanks for the video sir. Funda cleared.

[@lookosepappan4378]

Clearly explained, fantastic.

[@geenumaxy9370]

great explaination.thanks

[@mohamedroomy1985]

Very useful lesson sir jee. God Bless you

[@kunalsharma6976]

Thanks for sharing your experience n valuable...information Sir...

[@manivasagams7550]

Most valuable information sir. What type of Thermostat used in diesel engine sir

[@siddharthkumar7011]

thank you sir for such a great explanation ..and for relating practical knowledge with theoretical help in understanding the topic more clearly..thank u sir once again

[@amaranand2871]

Nice one

[@arunsingh-iq5hk]

Sir plz make vedio on angle decoder

[@abhaymishra16]

Sir please make one video on air conditioning system and problems and troubleshooting and your your videos are very helpful for understanding the concept of system

[@sailoroflife5431]

sir you are great

[@rmetcvideos]

Thanks. Also learning a bit by making these videos :-)

[@vardhaniattili4724]

Tq sir

[@kunalsharma9488]

Extraordinary sir.... I wished you have started the channel before i cleared class 4... Those who are appearing for class 4 are truly very lucky to have you sir... BTW i still watch your videos to clear my doubts.. Thank you sir

[@rmetcvideos]

Ha Ha. Learning never stops. Maybe I never knew most of the things when I was 4th ..

[@deepakshanmughan7928]

Thank you sir, was able to understand more about the thermostatic expansion valve . can you please help us by giving light on external equalising line and internal equalising line and why external equalising line is used?

[@abhishekbanerjee9425]

Informative video. Thank you for the explanation. Could you please also make a similar one of EPRV? I can understand the working of EPRV & TXV individually, but EPRV working along with a TXV becomes a bit confusing. Clarification would be highly appreciated. Thank you. Hope all is well during the pandemic.

[@rmetcvideos]

CAn you send the link of the circuit or manual.Since I have not worked on same it may be difficult to comment on this.

[@mohammadaslam9100]

🙏🙏🙏🙏❤️

[@kaushalupadhyay7404]

Again it is crisp and precise....Thank you sir. Sir ji there was an Ukrainian chief on my last vessel and he placed this TEV bulb on condensor arguably telling that there's no problem in doing so as there's was a problem of lot of icing on the suction line. I was not at all convinced but for my astonishment the icing problem got rectified for time being. But I was sure that it's not good practice. Can you please comment on this 🙏

[@rmetcvideos]

Honestly I wonder how is it possible to keep the bulb on the condenser..Correct me if I am wrong..I presume the condenser is near the Fridge and the TEV bulbs are inside the Rooms...🤔

[@kaushalupadhyay7404]

@@rmetcvideos sir ji this was done on AC unit

[@rmetcvideos]

Something terribly wrong..frosying on AC unit...was the suction pressure less than 2...some choke.

[@kaushalupadhyay7404]

@@rmetcvideos I don't remember exactly how much it was...but after a month compressor got kaput ...

[@lysonroy]

Thanks , one question if veg . Room back pressure value damage . What are the problems . We have no spare. How to manage.

[@medeepaksoman]

The video is really informative and knowledgeable. The effort you put in for the diagrams and animations is really appreciable. Thank you, Sir. I have a query though. What happens in the case of expansion valves with an external equalising line? My doubt is that, if the evaporator outlet line is fed to the bottom of the diaphragm, wont it be having same temperature and pressure as the gas inside the sensing bulb? If so how will it open the exp valve against spring pressure? Also I have read that this is used in systems with large evaporators where the pressure drop is higher; But if the ref gas is getting heated inside an evaporator how will the pressure reduce? Please explain sir. Thanking you in advance.

[@rmetcvideos]

Thanks for the question. The pressures bottom and top are NOT Same. The bottom one is LESS than Top one. Because the Top Pressure is the saturation pressure of gas at the Superheated temperature and the Bottom one is saturation pressure of the gas at evaporating temperature. The spring decides the temperature of Superheat.

[@medeepaksoman]

@@rmetcvideos Thank you for the reply sir.. The concept is clear now.. The pressure inside the bulb is corresponding to its saturation temp which is acting on the top of diaphragm.. 🙏🏻

[@ashishsharma8950]

Sir in the last part of the video as u mentioned if some refrigerants are heavier than lube oil they will disturb the bearing lubrication. Also refrigerants which flash off will also cause problem. Then what advantages do we have by connecting suction of refrigerant to the crankcase?

[@rmetcvideos]

If you directly take it to cyl head.. possibility of damage due to Liquid hammer will be very high. when you direct it to crankcase, only the vapours will go during suc stroke. The oil beoing at a high temp will ensure that the refrigerant liquid will flash as Gas. The Ref Vapors going inside the cylinder during suction will be OILY and hence Cyl LUb is enhanced. The entire compressor including the oil is Cooled due to cold refrigerant.

[@anshukumar-hz2sl]

Can you explain the function of EVAPORATOR PRESSURE REGULATING VALVE or Back pressure valve fitted at veg or lobby room evaporator outlet?? How it's work Why it is fiited and What could go wrong if it wouldn't have been there!!

[@abhishektalajiya1987]

Sir can u make a video on internal and external equalising line pls.

[@rmetcvideos]

In future..thanks..

[@avinashchaurasia7031]

Sir, the last portion of the video is quite confusing. We had taught in the classroom that there exist a pressure difference between compressor suction pressure and lube oil in the crankcase.

[@rmetcvideos]

Sorry on that...well,what you have learnt is correct..the suction pressure is normally the crankcase pressure and the lo pressure is over and above this...so if you see a oil pressure gauge showing a pressure of 3 bar and suction press is 1 bar then ..the actual LOP is 3-1 =2 bar. In many compressors the oil pressure gauge has two inputs..onw from pump line and another from crankcase...then this DP gauge will directly show you the LOP..hope this clears your doubt. Actually the video was not delving on this topic..it was only for liquid returning...

[@avinashchaurasia7031]

@@rmetcvideos yes sir, The video is helpful and interesting.

[@purushothamanrajaji1893]

@@rmetcvideos Good explanation...

[@seriousjack1]

Sir a question being asked in MMD nowadays that how to reduce meat room temperature beyond -20 degrees. If i reduce superheat will the temperature reduce beyond -20 degrees ?

[@rmetcvideos]

I guess the compressor should be designed to work at lower suction pressures..a combination of orifice and cyl/pisto designs..super heat definitely cannot be the answer

[@neyanmahizh4293]

sir how the temp of the room is changed can we change the room temp like changing temp in split ac room ,pls explain sir

[@rmetcvideos]

by adjusting the thermostat which starts and stops the solenoid valve

[@glesongomes9571]

Action taken if TEV not working?

[@rmetcvideos]

Change Ha HA

[@prakalpagrawal808]

Practically, do we need to clean the filter of thermostatic expansion valve?

[@rmetcvideos]

I have cleaned many times and honestly I have never seen it dirty :-). SO no need as a PMS...I guess

[@avinashhegde2777]

I have found the need to clean it on many vessels. I used dry electro clean ( non oil base). Another maintenance I regularly carried out was to fill the orifice chamber with the same dry electro clean. Close the opening with your finger and shake it vigorously. Now you press the spring loaded orifice valve from the bottom and allow the electro clean to pass through the orifice passage.

[@RajeshKumar-mt3pg]

Comment on 49 second is very funny

[@akshaybehera8196]

I beg you hahahahahahahah

[@rahulbhatia3481]

Thank you sir for giving valuable and practical knowledge .😀👍

[@rmetcvideos]

Thanks and welcome