HVAC 067 Subcooling notes

[@samsmith854]

I wish the teachers I had now had the enthusiasm to teach us like you do. Without all your info and others like you on KZbin I feel I’d be way behind. Thanks for what you do.! Glad to get an education from someone who cares.

[@americanpie8059]

Mr. Ty, just watching your content. I don't care if I think I know what to do by your video title, or if I've done it for years. I always like watching them. I also want to thank you for putting all your content out here on the internet. Some people simply do not understand why type of living they can make by learning a trade. Not getting in debt up to their neck in student loans, college tuition, and all the other costs for a degree. If you ask me, colleges degrees are filled with a lot of extra fluff. A good trade is a great way to go, and in the long run, you can work for yourself and not have to rely on a job to where you can be replaced at any given moment. Thank you again for all of your teaching videos.

[@michaelszczys8316]

Learned a lot of basic refrigeration principals 50 years ago, studied it here and there over the years, ( probably should have been HVAC ) but I am STILL learning stuff thanks to videos like this. Now my son wants to learn it, I hope to help him with learning these principals some which may be tricky to grasp.

[@Boojyman]

You're amazing 👏

[@honestman276]

Thanks from Bangladesh.

[@love2hvac]

I hope to visit Bangladesh one day!

[@Larrye123]

Foolishly started hvac school during covid when everything was online learning. Wasted $2,400 taking classes where I watched KZbin videos to try to figure out what I didn't know because I wasn't in a class room. This is the best I've seen so far. Wish my college did half as good.

[@love2hvac]

I built an online program for a school with the promise I would be able to travel and work remotely. Them covid hit and the videos saved their @$$. They made more money in 2020 than any previous year. Then a banker comes in and changes the school, throws away everything and band me from the campus I spent countless hours building. I never got paid for the additional time and work I put in. Including promises never delivered, lies, and stolen work, stolen and damaged tools, hundreds of overtime powers, they really screwed me over. So I decided if I'm going to work for free I can at least help as many people as possible. I also want to have a path for people to learn without having to be saddled with debt from for profit schools. So many of these for-profit schools rip off the instructors with $h!t pay, not providing the lab equipment or supplies while laughing their way to the bank.

[@amersingh2557]

Well said Ty, 😎

[@millenialmemoirs]

I left my stable decent paying management job for a small business in june 2020 and spent the summer unemployed and rethinking everything. Realized I wanted to learn a trade, specifically figured out I wanted to learn hvac but didn’t want to go to school with the virus and mandates. Landed an apartment maintenance job and learned so much working on Goodman heat pumps while watching Ty, Craig, Kalos, etc. been a selling technician for a year now and interviewing for comfort consultant positions now and looking to get my mechanical license. Learned so much from KZbin instructors.

[@staycoolwithrob]

You are making me a very good business owner thank you. You make it very easy to explain it to my son In a way he can understand.

[@wtfman5313]

These are the basics that I've had to fall back on (and nowadays, struggle to remember) when I was stumped. Good baseline information like this will help you eliminate what works and narrow down what doesn't.

[@toolemanful]

Great video thank you so much for you time and work

[@soultraneproductionz9180]

you're a very good teacher. very comprehendible

[@love2hvac]

Thank you

[@markjohnson9541]

Excellent...thank you. I follow your lectures and find them most beneficial.

[@love2hvac]

Glad you like them!

[@kennethlobo4420]

Great video! Yes taking notes helps.

[@thanhnguyen-su6bj]

good points and thank for the tips and a great instructor thanks

[@johnratrod9806]

Great information Sir. I appreciate your time making these videos.

[@AirsoftColeraine]

Great video Ty, very simply explained. I would love to hear more about non condensibles and system reaction/diagnoses. I have came across it many times as i’ve been on calls, and able to fix it, just never defined exactly that was the fault. usually high liquid line temp/high pressures etc. But would like to know more if you ever do a video as you are the master of explanations 😬

[@paulthompson1654]

HI ,,Many thanks your information greatly cleared up my auto trade teachings [ alot of incomplete theory buy not what u need ] subcool and super heat gotta luv them . Ideal low press R12/r134a low ac auto 20- 30psi/temp prevent freezing ,, high 150-180 psi /temp = properly cooled 100% refrigerant supply to evap . All this at 105f ambient . !! Try 270-290 psi down to 150/160 the system performed way better with 2nd condensor . Refer above . Sent bill to Ford ...LOL vent temp 45f doors open lol lol works really well Thankyou for clearing up my auto teachings . As u may no auto are very poorly designed systems compared to commercial fixed plant .

[@davidmorrone8783]

Awesome once again. You are in a class of your own dude. I'm not a tech but i love getting educated on this subject matter so at the very least i can carry on an intelligent conversation with a tech coming to do service work on my projects. Thanks again.

[@hkhsm359]

Nice video. Thanks for sharing your knowledge

[@deanmartin1966]

Another great video. Thanks for sharing.

[@logan4215]

Thank you!

[@jaymartin5095]

In earlier lessons you talked about causes in terms of the state of both the condenser and the evaporator. In this lesson you talk about superheated and sub-cooled vapor separately. Is one to assume your list of causes for each is based on the other side being at target? Thanks and thanks for putting these lessons online.

[@blacksmith8642]

Good 👍

[@alyciadh32]

Thanks so much!!

[@staycoolwithrob]

Thanks bro

[@andrewd1795]

Hello Ty. As i mentioned before these are great videos and they have helped me whenever I needed some clarification. Question for you In the previous video about superheat you mentioned dew point for Suction. When dealing with subcooled liquid would you be looking at the bubble point instead?

[@love2hvac]

Dew for superheat (superdew to the rescue) Bubble for subcool (Sean Connery in red october 5 degree down buble)

[@michaelruivo601]

Low ambient with no fancycling will cause a starved condenser…. Adding to low sub cooling due to the condenser being too efficient. Even with fan cycling in low ambient the artificial load on the condenser does not raise subcooling just head pressure. There’s just such a major swing in pressure, full column to no column of liquid if you pay attention to a sight glass. Pressures must be stable for Atleast 15 minutes for true readings.

[@haimt]

Hi Mr Branaman, can you please answer my question: what will append to AC condenser (in summer mode) at low ambient temperature to the amount of liquid refrigerant?

[@love2hvac]

Usually the condensor will flood to build the pressure needed.

[@broelbox3317]

do I understand correctly that the low subcool indicates that there is no proper heat exchange in the condenser, and the high subcool that the condenser is too much air cooled(too big temp. drop)? When there is a low subcool, is there too much vapor in the condenser and condensation is too late?

[@heatingairservices8708]

Hi Great Presentation on SC with an TXV EEV fuly understand find target on maunf Data plate or otherwise but Iam slightly confused on Fixed orifice starting SC ..Not SH while SH is Super important Right !!! but @ the moment its SC lesson . .. BUT @ around 6:33 to not sure where its ends 6:45 maybe but ur saying SC will be much higher with lower ODA tempt & also seconds after u said SC will be much LOWER with Lower ODA if I herd you correctly that is...... so slightly confused witch makes Higher SC 70 day or 95 oda ..for an fixed orifice Day Thanks

[@love2hvac]

With a fixed office we focused more on Superheat but we don't ignore subcooling. If you look in the playlist Learn HVAC these videos are in numerical order. I have videos specifically demonstrating how subcooling works with a fixed orifice. I will put it is a few words but the video does a much better job explaining with visual effects. With a fixed orifice, as the outdoor temperature goes up the pressure goes up. There is now more pressure against the liquid so more liquid is pushed through the fixed hole. More liquid is pushed out of the condenser so the subcool liquid quantity drops. As the outdoor temperature drops the pressure against the liquid drops and less liquid is pushed through the fixed hole. So subcooling in the condenser goes up.

[@gearstil]

hello, why a dirty condenser coil will cause a low sub cooling? As it heats up it will increase the pressure and the refrigerant will condense faster...Am I missing something?

[@love2hvac]

The dirty coil dosen't transfer heat as well so the convincing temperature and pressure rises. The higher pressure pushes the liquid out of the condenser faster on a fixed orifice.

[@gearstil]

@@love2hvac I got it, thanks!

[@thanpan1276]

If you are not able to see subcool note on the "Supporting Document" link using computer, then use your smart phone.

[@realSamAndrew]

Ty, around 6:30, you seem to mis-speak, you say higher subcool lower outdoor temp, then you say lower subcool at lower outdoor temp, the opposite for the same thing. Can you clear it up?

[@love2hvac]

Thank for brining that up I will check as soon as I get back to a computer and let you know. It will be a few days.

[@fabiodarocha2842]

Is it better to do the wet bulb in the ductwork by the return or out of the ductwork?

[@love2hvac]

I prefer to do in in the duct close to the evaporator if there are multiple returns. If its one return it should not make much difference especially in a closet unit. A leaking duct in an attic would make a big difference.

[@fabiodarocha2842]

@@love2hvac thanks ty👍🏻

[@garypoplin4599]

1:50 - “Red for submarine”?! I thought the submarine was yellow!

[@love2hvac]

The Hunt for Red October was about a submarine

[@garypoplin4599]

@@love2hvac Sorry, I had the Beatles on my mind. Thanks for that blast from the past!

[@love2hvac]

@@garypoplin4599 I did a spoof remake a red submarine song to help students remember it but the beetles copywite keeps taking it down even though it falls in the fair use rules.

[@RBaldwin58]

Anyone have any ideas on what can cause a 4-ton split system in Phoenix to cool perfectly (good superheat and subcool and temp split) when it's 105 or below, but once it gets to 110 outside the temp split drops to 11 deg. It has a TXV inside and outside (heat pump). Sensing bulb is mounted correctly. Inside temp stays about 79-81. Weird one for me.

[@thisisyourcaptainspeaking2259]

Was the charge weighed in, bla, bla? Sounds like an issue with indoor txv. Gas type is 410a? 410a critical temp is 160F, right?

[@goldstarhvacrllc2567]

What are the actual temps coming out and return in your air supply?

[@robertcherry4971]

Yes it’s AHRI ratings are 75 degrees inside 95 outside . When you fall outside the realm of these temps you will drop off accordingly .In other words if you want it to keep up you need to increase capacity or decrease load.(think insulation ) or such.