Refrigeration Basics with Elliot and Bert Part 1
In part 1 of a series on Refrigeration Basics, Elliot and Bert team up to teach a class about refrigeration basics. They discuss the basic scientific principles that make HVAC systems work and how they work with the components most residential HVAC systems will have.
There are four main components: compressor (high-temperature; pressure increaser), condenser (heat rejector), metering device (pressure dropper), and evaporator (heat absorber). When you start by memorizing components and their order, you can start to absorb information about HVAC systems with greater ease since you will have the vocabulary at your disposal.
Pressure is one of the main driving forces of the HVAC refrigerant circuit; it is the force exerted on an object. It may be measured in absolute pressure (PSIA) or gauge pressure (PSIG), the latter of which deducts atmospheric pressure (14.7 PSI). We usually use PSIG in the field; we may use PSIA for some PT charts and calculating the compression ratio. In the HVAC industry, we primarily measure air pressure in inches of water column ("wc or in. wc.), refrigerant pressure in PSIG, and vacuum pressure (in microns; 1/1,000,000 inches of mercury column).
Temperature is an average measurement of molecular velocity (how fast molecules are moving). It is not the same thing as heat; heat is the amount of energy a substance has, not the average speed of the molecules. Something may be cold to the touch but still have heat. In the HVAC industry, we are moving heat; temperature is an indicator of it, but it's not the exact same thing. Temperature measurements might be wet-bulb or dry-bulb. Dry-bulb temperature only accounts for sensible heat, and the wet-bulb temperature accounts for latent heat (moisture or humidity) and is usually cooler than the dry-bulb temperature.
The compressor manipulates temperature by manipulating pressure according to the Ideal Gas Law (PV = nRT); as pressure rises, the temperature also rises. Temperature also decreases as pressure decreases, so the metering device drops the refrigerant pressure before it enters the evaporator again.
The Second Law of Thermodynamics states that hot goes to cold; heat moves from hot to cold and will attempt to continue to do so until both objects are at the same temperature (thermal equilibrium). HVAC systems use the evaporator as a means of heat transfer; heat from the space is moved into the colder refrigerant, and refrigerant that is hotter than the outdoor temperature gives off that heat to the cooler space. Imbalances in pressure will cause the refrigerant to move, and imbalances in temperature will allow heat to move.
Voltage, or electrical pressure, also follows a high-to-low rule. Whenever there is a difference in electrical potential, electrical energy will move from a higher concentration to a lower concentration due to the energy imbalance.
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Read all the tech tips, take the quizzes, and find our handy calculators at www.hvacrschool.com/ or the HVAC School Mobile App on the Google Play Store (hvacrschool.com/play-store) or App Store (hvacrschool.com/app-store).
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Well done - illustrated 👍 and explained.👍
Simply these gentlemen reorganized my big picture into the most detailed knowledge in less than a hour! Thanks a lot.
Thanks for the teaching and I'm glad to be here cuz every information is of essence to me and I am a HVAC practitioner...from Liberia a western African Nation 🇱🇷🇱🇷
I’ve never been involved with anything related to HVAC or refrigeration outside of cleaning my AC filter, but these guys have an excellent classroom culture. A true class act from both teachers. Bravo
It’s so good with two teachers. Two different perspectives. Love it
Kalos Enterprises, HVACR School, greetings from Canada here, Mr. Bert, Mr. Elliot, Mr. Bryan. I appreciate a lot for the information. You guys get deep into this information. I would ask you gentlemen to do something for the northern side that is Canada in case there is anything. Well appreciated guys.
These guys hopefully appreciate the team of people they have around them.
Informational video, also lead instructor is Ben stiller in disguise teaching hvac
Very informative. These guys are great together!
VeryGood teachers , excellent attitude hands down .
"I wasn't listening" -Bert LOL
That was awesome. Thank you so much.
From Kenya.... waiting for part ll
Great work!
Ty guys! Great content. Nice to see Bert doing his thing.
Essentials made easy!
New learner here😊
Very good explanation
14.7 PSI
Hello from Arizona
Ideal gas law IS useful!!!
What y’all doing in Destin Florida? Seen one of your vans
Berts back!!!!!!!!!!
Unfortunately, the presenters have mislead the students by saying that the compressor doesn't impart energy to the refrigerant. A low pressure, low temperature gas comes in and a hot, higher pressure gas exits. Energy must have been supplied to do this! A simple example should help - when you use an old, hand held bicycle pump the tire and the pump will heat up. The "pumper" does work on the air and this results in increasing the air's energy and hence its temperature. One additional comment: I think it would be nice if, in Part II, you explain the molecular reason why the metering valve cools the refrigerant. Even though I've been critical, I would like to say that Kalos does a great service to the HVACR community and wish that more companies were as honest and knowledgeable as Kalos.
Good video when is part 2
@borshardsd
20 күн бұрын
Lol the future is coming. You asked what I was thinking fam!
@HVACS
19 күн бұрын
Next instalment is going to be published on wednesday, tune in!
@xaivergb
19 күн бұрын
Good no hockey game that night now I have something to watch.😁
Cool stuff. I'm trying to troubleshoot a roof mount packaged unit at my parents house but find myself going down rabit holes.
@denverbraughler3948
21 күн бұрын
What measurements have you taken?
@zero2three1
21 күн бұрын
@@denverbraughler3948 I replaced the chinese capacitor that was about a year old with an Amrad 45+5 370/440v. Both tested fine. Didn't test under load though. Should have tested before replacing (now have a spare). I can hear the compressor but the fan isn't running. Going to bypass the thermostat and see if I can rule that out. Learning as I go...
@matttzzz2
21 күн бұрын
Might be ADHD? I had the same issue until i fixed it
@BlackAutumn08
21 күн бұрын
Indoor or outdoor blower?
@miguelperdomo786
20 күн бұрын
@@zero2three1 Your thermostat does not control the outdoor fan, when the unit is running check to see if you're getting voltage to the fan at all😊
From Turkmenistan
BERT LIFE BEACHES!
Hello from indonesia
* Physics. If you have interesting chemistry going on, something is going wrong.
Hello from libya
From India
From Ukraine
@denverbraughler3948
20 күн бұрын
Яке місто?
@klimat_montag858
20 күн бұрын
@@denverbraughler3948 Привіт. м.Чернівці