Hot Gas Bypass Valve Application and Low Load Conditions

[@HVACKnowItAll]

I love hot gas bypass valves 😆

[@abazism]

Can you please make a video on head pressure control valve please.

[@drew2276]

i get my gf to run flat after I raise her temp by backing out the screw through an open device, I screw in and out to back tension off, I have some superheat added into that, it gets warmer less chance that will cycle off, and back to normal conditions naturally on its own. I back off again and discharge my load in the theater. the load drops off because the body heat is gone. but I set for that. so that in a nutshell is how I adjust her full capacity attitude and generally a good example of an application of that. happy HVAC guys!

[@phrodendekia]

👏🏻👏🏻👏🏻

[@robertmalone9699]

Your explanation was thorough yet simple and to the point. You didn't try to crowd too much information into video.

[@HVACKnowItAll]

Thank you sir

[@renecuevas4128]

I see and read most of the comments Most guys understand quick. Others have No clu n got it confused w Txv. U explain it clear. I m not American n clearly understand ....fl weather around 60 s Good time for LAT and Low Load u put an easy Movie Theater example. Tnks n blessings

[@NotThatGuy_YepThatGuy]

I struggle with mechanical load and ambient control. Specifically the applications of Hot Gas bypass and Headmaster Valves. I mostly understand what they do, and why, but i have the damndest time troubleshooting if they are the problem. Thanks for this video. Long time watcher, seldom commentor.

[@chrisnorris1959]

Thanks Gary! Great explanation. Watching this video will make the actual Sporlan literature for these valves easier for me to digest.

[@HVACKnowItAll]

I love hearing that, thank you

[@VapourRose]

We use the same pipe set up but use a rapid cycle solenoid and no HGBV to control really tight temperatures in our environmental rooms.

[@HVACKnowItAll]

Cool!

[@MistaWhatchaKnow]

Do you use a PLC to control the toggle cycle of the solenoids? Or is it controlled by a relay?

[@VapourRose]

@@MistaWhatchaKnow we use a Loop controller and a relay to cycle it on and off. Company be buy the controllers from is called Future Design control and its the R-22 controller.

[@MistaWhatchaKnow]

Thanks! I took a look at the website and the controllers they offer. Never heard of this company, but they type of controllers look like a nice drop in for Watlow controllers. I really like the Watlow controllers, but they are very expensive. Most customers don’t need the amount of features either. What I have found out is toggling solenoids works well, however some size units need an adjustable valve inline with the solenoid to meter the amount of hot gas entering the evaporator. This way to can adjust the Hot Gas Bypass Valve to the exact PSI that you want. I watch the controller to see the temp swing. I want to mention that Hot Gas is not greatly energy efficient, although the machines run really well when not cycling and can maintain a consistent temp inside the evaporator. We can hold a temp of -+.5 degrees on oil and water cooling. This helps our customers achieve ultra precision in their processes.

[@mikhaielj846]

Thanks so much needed this for tomorrow’s job

[@epicone2449]

Great videos man. Listen to your podcast too. Thank you for what you do for the trade

[@HVACKnowItAll]

Thank you, doing my best haha

[@mikefreedom5612]

Good video! It's a way to balance the load on small refrigeration systems

[@daviddesilva4971]

Great explanation on the hot bypass valve. Thxs for the vids!

[@HVACKnowItAll]

Thank you and my pleasure

[@michaelbalke2314]

Great explanation of the system!

[@HVACKnowItAll]

Thank you

[@Jeff-Lawrence]

Love this style of vid. Great work

[@HVACKnowItAll]

Thank you I appreciate that!

[@mdmuntasiralam774]

Great demonstration! Thank you very much. What's the purpose of the pressure equalization line here?

[@shockiller465]

Thank you sir; Great Video keep up the good work

[@bhunter3850]

Thanks for the knowledge. I think I’ve learned more from your videos than my coworker who considers himself a “super tech”.

[@HVACKnowItAll]

My pleasure. Lol!

[@shanegreen268]

Thank you for sharing your knowledge. Great video

[@HVACKnowItAll]

Thank you and you're welcome

[@shanegreen268]

@@HVACKnowItAll you bet..

[@sdsd4284]

So technically its job is similar to a epr and a headmaster ? Great vid and EXPLANATION btw u make it very understanding.

[@HVACKnowItAll]

Not really a head master maintains head for low ambient and an EPR is on the outlet of the evaporator

[@sintongbutarbutar8478]

Very clear explanation, thx

[@HVACKnowItAll]

You're welcome

[@abazism]

Wow very well explained.

[@janeilquino2599]

Good day sir.thanks for information very clear explanation

[@mr.fahrenheit723]

This is a great video!

[@HVACKnowItAll]

Thanks

[@neilvestervictor180]

great information knowledge is the key to success

[@HVACKnowItAll]

Yes it is, thank you

[@neilvestervictor180]

I am a chill water technician from st Lucia

[@HVACKnowItAll]

Lovely weather I bet!

[@neilvestervictor180]

yes sunny in the Caribbean with a little rain in between you should take the trip on a vacation lol

[@HVACKnowItAll]

Yes but our conrona restrictions re-entering are crazy so no traveling for a while.

[@TheLinkIsLost]

Very well explained. Thanks!

[@johnpolos8796]

Have you worked on environmental test chambers and chillers?

[@nimbo9492]

I have seen some hot gas bypass lines connected to the suction line (in between compressor and evaporator) as opposed to inlet evaporator like in this video. How are they exactly different?

[@renecuevas4128]

Same question i got when i see his Diagram seems like same Line ......but doing different case scenario as he mentioned Movie Theater....Low Load versus LAT make sense i guess ....

[@chantaledamiengatien725]

Hi, Great video ! I have also a hot-gas bypass valve on my LG multisplit, but it is bypassing directly the compressor's output to the input of the accumulator (just before the compressor input). When the hot-gas is activated, for example when a split is stopped, I can see the high pressure decreasing and the low pressure increasing. However, what is strange to me, is that when the hot-gas is deactivated after 30 seconds, the high-pressure recovers quite fast its initial value, but the low pressure is dropping much lower than its initial value (for example, from 8.3 bars to 6.7 bars) and seems to stay at this lower value (until the outdoor unit regulation is changing the inverter compressor speed). Do you have some explanation why it behaves like that ? I am not really sure that it is normal since it is generating periodical fluctuations of the regulation :( Thanks a lot and regards

[@chova210]

Well explained 👏

[@syedbasheer8210]

Good explanation👉

[@HVACKnowItAll]

Thank you!

[@mahmudnady1859]

Thanks for the information

[@juvaeljadman2296]

Good day sir. What is the actual low pressure of -10 and what is the deffirential walk in chiller. Thank for your help

[@natepeterson7145]

Well done!

[@HVACKnowItAll]

Thank you

[@simohvac9222]

good explanation thanks

[@HVACKnowItAll]

You're welclme

[@mematyi]

Great Explanation! Could you make a video explaining the difference between this Hot-gas bypass valve method and the Evaporator pressure regulator (Danfoss KVP)? Is it technically the same?

[@sholapuramtoday1596]

If discharge high pressure and high temperature that time not use this please explain

[@Sigmameals]

Will you be able to put what you explained on a PH diagram or in equation forms using thermodynamic cycle?

[@mrgreen9086]

Great explanation is this system factory or do some components needs to be field installed?

[@HVACKnowItAll]

Both

[@mrgreen9086]

@@HVACKnowItAll thanks for sharing

[@herbertfynnwilliams5177]

I have questions? am working on a unit that has hot gas valve when you put the unit on the temperature is able to come down to about 19/c but when the hot gas comes on you have the temperature reading 23 and it doesn't come down any more

[@HVACKnowItAll]

These are room temps? Hot gas is for low load conditions. It needs to be set to supply hot gas when the load and corresponding evap pressure falls off.

[@ollirbasepeacefulmusic6508]

Why you don't see hot gas bypass to use as defrost in domestic fridge or freezer? My dad use to have an old fridge with hot gas bypass defrost

[@محمودحمدي-ظ9ظ]

Can i replace the sporlan hot gas bypass valve with a solenoid controled by a digital tempreature sensor The sensor will measure suction line temp and control hot gas bypass valve

[@stefanocubero6367]

Thanks man!

[@dinushakumara4580]

is this condition liquide refrigerant may be come back to the compressor

[@bradmironik6137]

Good video. I follow on how the hot gas creates a load on the evaporator but is there another component after such as an accumulator to return the refrigerant back as a vapor? I haven't seen this setup in the field before. Thanks.

[@HVACKnowItAll]

There is never a receiver after an evaporator, the receiver is after the condenser. It's still returning as a vapour, the discharge gad is highly superheated vapour

[@HVACKnowItAll]

Sorry my bad, thought you said receiver but none the less no vapour will get back during hot gas byapss

[@bradmironik6137]

Thanks for responding. So you are saying the hot gas in the evaporator has some heat removal but not to the point of changing state? Therefore vapor still returns to the low side of compression.

[@capitolrefrigerationheatin7501]

@@HVACKnowItAll I see accumulators after evap to catch any liquid,saves compressor from slugging

[@Username-ng8jy]

Yes those are common in refrigeration. I used to do commercial refrigeration. It was a vital component especially freezers where the coil must be flooded with liquid for below zero temps.

[@oriansinkleryukon2680]

What actually shuts cooling down will the hot gas bypass continue to run when show is over

[@HVACKnowItAll]

If it hits full on set point, the system will shut down. The hot gas will stop feeding on the off cycle.

[@sumantaparamanik7863]

It can be use Blast Freezer? Plz explain me

[@fret2fret221]

The way you explained this sounds like it operates similar to a TXV...

[@Username-ng8jy]

Nah dude. Nothing at all lol. A txv is there to throttle liquid into evap to provide cooling. This is just a valve that allows heat to enter the low side to increase pressure a bit when there is no load.

[@723lion]

HGBV is for tight temperature control.

[@arazqurbanov8162]

Salam size bir sualim var? Valve soyuq hava seraitnde isleye biler

[@maheradous9257]

Good job

[@ramilolanda8517]

How do bypass valve of expansion valve works?

[@peterrivas08]

Really good video but could you or someone please explain the difference between this and a headmaster valve? Are they essentially they same just different terms? Thanks

[@ES-ml4cg]

Headmaster or OROA is for head pressure control at low ambient conditions.

[@peterrivas08]

@@ES-ml4cg thank you for the reply. Sorry I'm just confused, but why do you need to keep the head pressure up? So the low side stays up as well?

[@aircooledchilleralltypes4938]

But what is the function of the equlizer line

[@andrewnolan8449]

One of the very important part on hot gas defrost missing …

[@HVACKnowItAll]

This is not hot gas defrost, it's hot gas bypass

[@joeschneider67]

Thanks

[@HVACKnowItAll]

My pleasure

[@pangmlrani5200]

Does the compressor delivery pressure becomes less when bypass valve is open?

[@HVACKnowItAll]

No it becomes more, it's adding pressure the to suction line

[@HVACKnowItAll]

But on the discharge line the pressure will drop a little, sorry, not exactly sure what you're asking.

[@Sorcerers_stash]

Good stuff

[@HVACKnowItAll]

Thank you

[@fret2fret221]

The guy training me saw one of these the other day and legit said “I’ve never seen anything like that before...” 🤦‍♂️

[@tonydellapennajr2681]

You're dragging the guy training you because he hasnt seen something?

[@harendradangwal6382]

Hot gas bypass valve in Air dryer not allowing to transfer the Cold refrigerant into evaporator why? transfer hot refrigerant into evaporator

[@mkamal2892]

how does hot gas bypass work??

[@HVACKnowItAll]

That was explained in thr video

[@Boz1211111]

seems like it wastes energy not to cycle compressor?

[@jasonjohnsonHVAC]

RAWAL DEVICE WOULD BE GOOD IN THIS EXAMPLE

[@arazqurbanov8162]

Salam

[@Coonhoound89]

Awesome

[@josebetancourt6866]

Easy explanation. Thanks 👍

[@fret2fret221]

The way you explained this sounds like it operates similar to a TXV...

[@HVACKnowItAll]

Not exactly, TXV opens on a rise in bulb temperature. A hgb valve opens on drop in suction pressure.