Online HVAC Training - Metering Devices

[@PurpleHeartVet11B]

I am a hvacr student and last friday my instructor kind of hit on the TXV, but in no where near as much detail as you have done here Ron!! thank you for clearing things up a little for me!!

[@RonWalkerHVACTrainingSolutions]

PurpleHeartVet11B You're welcome! And thanks for serving.

[@johnyoung-i3g]

The compressor unit seems to be working and the liquid line gets cold sometimes at the evaporator, but the suction line is warm from the evaporator back to the compressor , why?

[@bodybuildingking]

For all the dolts who gave up on the video because of the distorted audio: it starts around 7 or so minutes and goes on for 10 minutes and comes back to normal. With the video being 54 minutes in total, it still teaches you a CRAP TON of information that only a fool would walk away from. For me, I could still make out most of the choppy stuff; So I lost about 5 minutes out of 54 minutes. Big deal! I still understood this way faster and better than anything anywhere else. Excellent video!

[@irshadakhtar2290]

earlier I had some doubts regarding control of superheat....today all doubts r clear thanks bro...

[@hvac877]

Yes me also

[@vakeadaia5333]

Thanks Ron, very helpfull.

[@samdee4563]

Ron walker your video was very informative..thank you for that!..i have a question for you!how do you charge blended gases ? why the manufacturer encourage us to charge liquid only?..i mean the newer gases type?

[@JAMR0716]

+sam dee The reason why manufacturers encourage HVAC techs to charge blended refrigerants in a liquid state is to prevent fractionation of the refrigerant mixtures. You can get more information on this in articles on the internet.

[@jameshohimer2542]

At 27:43 Superheat is in degrees not psig as stated.

[@haneefmsqaazi]

You are an excellent teacher and your tutorials are some of the best on this topic. However this particular clip has been recorded badly and the audio is not clear. I wonder if you would consider rerecording this video and make it available on KZbin. Thanks for your help all the same.

[@ShawnMichael121277]

You say that the TXV takes 15 minutes of run time to stabilize and start working properly. Unless I'm mistaken, 15 minutes of continued running is inefficient for a residential application isn't it? Would it be safe to say then that TXV's aren't ideal for residential? If so, are the new units with TXV's using a different design?

[@Tuff-mr7cp]

Can you redo this because the lesson came out garbled and distorted. The video stopped............I will look for another diagram thanks.

[@RonWalkerHVACTrainingSolutions]

Tuff 2015 Yes, I will check it out and shoot a redo. Thanks for the heads up... (I never watch them back)

[@hvac877]

Wow superb please suggest me sir I have Dx system but always oil problem in pipe and always compressor be ground please please please suggest

[@vlajko8000]

When you are talking about force equilibrium ( spring, bulb, evap. etc.. pressure) why do you exculde the force that is acting on the orifice from the condenser side (condenser pressure)?

[@poochpoints]

advokat hadzitonic good point

[@ShawnMichael121277]

Second question: I'm struggling to see the benefit of the TXV. The TXV can regulate the refrigerant flow which I assume allows the compressor to shut off, right? Wouldn't that be the only efficiency benefit? But surely the compressor isn't shutting down and restarting numerous times throughout the on/off cycle as the indoor temp drops. So what is the point? Just to let less refrigerant through even though the compressor is continuing to run? Is it bad to allow the compressor to run without allowing the refrigerant to flow?

[@1221Genocide]

+ShawnMichael121277 the txv does indeed regulate refrigerant flow but it does not allow the compressor to shut off. The compressor is the heart of the system and if it shuts off all refrigerant flow will soon stop. The compressor stays on the whole time throughout the cooling cycle until the desired temperature is reached at the thermostat. The TXV helps the cooling process, without it there wouldln't be any cool air in the evaporator coil in your house and the system wouldn't work. Yes, it is bad to allow the compressor to run when the system is dry.

[@ShawnMichael121277]

So how is a TXV more efficient/better than a standard orifice type? If the compressor is running constantly for both, I don't see the benefit. Especially when considering all the horror stories I have heard about TXV problems with clogging, etc.

[@timsky99]

+ShawnMichael121277 With TXV's it's about the percentage of the evap that contains liquid which can remove latent heat from the space. Under heavy load the liquid boils off quicker and so there is only vapour left which is not efficient. So as the bulb warms up it lets more liquid through because it has a higher pressure than the spring and the evap. As the space cools down there is less heat to remove..the TD between the liquid and the return air gets smaller...so the bulb gets colder. This causes the valve to close down. Any compressor will run until the set point is achieved, the TXV is all about balancing the portion of the evap that's flooded and that gives you the superheat. Not enough liquid - SH too high, too much liquid- SH too low and you get compressor problems among other things. The valve never fully closes off, on or near the set point is the time when the system is under the lowest load and so it follows that not so much liquid is being boiled off, and the valve closing down allows for that. I don't see many fixed orifice systems in my travels, but loads of TXV's and they work fine. Once you get your head around superheat it all becomes clear. Also any system with a TXV will have a liquid receiver so can be pumped down, making working on them not too bad as in checking for blockages....it's just 2 spanners and a nut.....they don't block that often and usually it's moisture which affects any system regardless, or it's carbon from where people have been brazing without using OFN

[@Flynntastic]

They are used in multiple evaporator systems

[@andremaharaj567]

the fan from the condenser pushes the heat from the tube to the outside

[@daviddebord7236]

Greetings Ron What would cause a "Wailing noise like a Gerbil getting choked" to come from a TXV AACE5HW100 upon start up of the Heat Pump. Within 2-3 seconds this noise disappears. This unit is absolutely not presenting any further "Known Problems".

[@seanzuber69]

Thank you this video helped me alot

[@tboneproductions2453]

Excellent info. Thank you

[@大香的双国记中国和新]

Thank you !but the audio is broken ...

[@resandor]

This looked like the one video that was going to clear my confusion...then the audio broke up. Screams!

[@RonWalkerHVACTrainingSolutions]

Arrrgh... Sorry, what is your confusion?... I'll see if I can help.

[@resandor]

Ok. Let me start by saying I'm a new hvac student (2nd week in school). I'm trying to fathom how 75 degree air can travel over 40 degree coils and go through the duct at 55 degrees so quickly. I understand that when evaporation happens in the coils it absorbs heat. I hear the information but my mind just can't grasp it yet. I need a better understanding and visualization of how this absorption happens. Your video was awesome btw I just couldn't hear the audio.

[@euntal5255]

Is it true that relationship between velocity and pressure is the basic principle behind the capillary tube metering device? The smaller diameter of capillary tube causes any fluid to increase its velocity and causes pressure to drop until the boiling pressure (liquid to gas chart saturation point in a PH diagram) is reached causing a phase change, i.e., turning liquid to gas . This is best explained by the Venturi meter.

[@luisLopez-uz3mv]

awesome channel am a new subscriber !

[@cneturytwenty6794]

Thank you for the video

[@RodMoorewithDeb]

As the lectures goes on. The audio becomes useless.

[@The567567567]

The audio broke up in the video

[@alconk7129]

Please do something with the audio....

[@marktrana5286]

the audio is bad.

[@poochpoints]

Very instructive, just have to get through the janky audio in the first 5 minutes.

[@RodMoorewithDeb]

The lecture might be good, but can't tell. The audio breaks up terribly.

[@RonWalkerHVACTrainingSolutions]

Sorry Rod, I get that fixed.

[@Potshot3]

Audio is still terrible.

[@gearhead0800]

I think we should stop complaining about the audio after all it's only 1967 isn't it?

[@stephanedoyon8531]

Sorry, the audio is very bad!

[@esalmons9063]

Audio is horrible. Makes the entire lesson a session of guess work. Otherwise this would be an execellant teaching tool. Too Bad...

[@robinfrancis2911]

91 psig - 67 psig = 14 psig ???????? Uh!!

[@Fernandesfo]

Vídeo Baixe animação Tecnologia Economizer em HTML5 e Flash kzbin.info/www/bejne/rKq4gn5nfa2fZ9k

[@Betoven81]

nice

[@oscarpz11]

Is it me or did he fart at 6:32

[@pradyumnpatel4963]

Patel

[@teddyacosta]

men if you really care about teaching you should redo this video it doesn't matter if it get better later is still anoint to watch

[@oso1165]

Its freaking witchcraft

[@pradyumnpatel4963]

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