Air Conditioning Diagnostics Part 1: How the System Works

You’ve been waiting patiently and it’s finally here. This series will be so beneficial for all techs who want to better understand AC testing. The Professor will walk you through every step during this series and it starts with the basics. In order to be able to test properly and repair the systems you have to know how they work. That’s what we cover here. Hope it helps! Enjoy!
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[@CodycoWeb]

Using infrared guns take a piece of black tape and put it on the shinny lines and you will get better readings. Great series to help techs fix systems.

[@ThunderbirdRocket]

Nice 👍🏼 ! Thanks !! 👊🏼

[@DuanesDiagnostics]

Good tip!

[@michaeldiaz6308]

This is definitely helpful, Doc. Hoping part 2 is coming out soon. Unless I’ve missed it. I wish I could pick your brain or get your input on a ‘24 Corvette that is freezing at the TXV and at the compressor.

[@wonka-je8mw]

Thank you for this. As a tech who has done AC work for 10 years a refresher is always nice to have as we all pickup bad habits over time to speed things up and don't always properly diagnose an issue and just throw a part at it which works good enough but doesn't fix the issue.

[@dabofiron.itzsimplicity]

This is incredible, been wanting to learn AC for a while! Thank you!

[@Conservator.]

16:18 The evaporator core gets cold. Air passing by the evaporator will cool down. Cold air can absorb less moisture than warm air. Therefore some of the moister that was absorbed in the warm air will condensate *on the outside* of the evaporator. If there’s a lot of condensation it will be drained (some cars will ‘leak’ water on hot days. They don’t really leak water, that’s just condensation) There’s no direct contact between the air that’s cooled/condensation and the refrigerant. So no moister will go from the air to the refrigerant. So the refrigerant does not pick up water from the outside air. Just my 2 cents. I’m looking forward to part 2!

[@niallseddon8657]

Also, here in Scotland for sure I would expect to see moisture on the outlet pipe from the evaporator, similar to a picture of the evaporator if we could see it.

[@stevef7968]

Looking forward to part 2!

[@chrismoffitt9873]

Great presentation! I really appreciate your time and effort. I really love your channel because you explain EVERYTHING. You really hit the nail on the head when you said that if you can understand how something works, you can fix it. Description of the system and theory of operation is the first thing I go to when I’m diagnosing a system I’m unfamiliar with

[@marlinyoung1606]

Man I am excited for this series.

[@davidmoss9471]

Really looking forward to this series, a great first installment there thankyou

[@malibuStroker]

Fantastic video!!! Can’t wait for part 2!!

[@8power0]

I NEED THE HELP ,,, THANKS SO MUCH AND LOOKING FORWARD TO THE REST OF THE SERIES THANKS AGAIN !!!!!!!!👀🙏🙏👍👍👍👍👍

[@SeilerRdAutoCare]

Just bought my first set of gauges. Trying to learn more about a/c systems right now. Mainly what to look for when troubleshooting. Thank you for putting this together for everyone!

[@CodycoWeb]

Please hook your gauges to known good systems and look at readings. You can do things like temporarily block the condenser with cardboard or disable the fans and see how the pressures react and well as measure the lines and see the temp differences both ways. Maybe let a little refrigerant out and see pressure differences and then add back too much and see what overfilled systems show on gauges. Have fun and enjoy what you can learn.

[@SeilerRdAutoCare]

Those are good things to try, thanks!

[@martinboucaud679]

I love it, I love it, great job guys. I learned something new.

[@johnboutsikos6049]

Great presentation a mention that one is a high pressure gas which becomes a liquid when it goes thru the orifice or expansion valve then back to a gas in the evaporator .

[@James-fs4rn]

👍 very helpful. Thanks for sharing! Keep it coming please.

[@Quickwrench75]

Great video. Nice breakdown of A/C Hope younger can listen You Made is easy to understand Keep vids flowin !

[@CodycoWeb]

Dryer conditioned air is due to the condensation on the evaporator removing humidity from the air passing over it. There is no absorbing of moisture by the refrigerant. It just absorbs heat. Side note it doesn’t cool the air it makes it less hot. 😊

[@DependableAutoTruck]

great information what you are doing is good. back in the 1970s i worked for Montgomery Wards we installed a lot of in dash and under dash units. those units were 12 and boy they would get cold. i have seen so many changes thru the years now we have those variable displacement compressors. you really have to look closely to make sure what type system you have to be able to fix any A/C unit. old days simple they didn't have blend doors to mix hot and cold air you either had heat or ac so easy do diag. thanks for sharing this information wonderful reminders

[@adampietrzykoski7344]

Very well explained!

[@coldfinger459sub0]

Good basics demo. I’m really glad to hear you mention about variable displacement, compressors, having clutches.. Some old-timers or young guys who read old literature are stuck in their head that only clutchless compressors are variable. And they’ll actually try to argue the fact.. How many technicians and shops try to top off refrigerant on variable, Displacement compressors shooting for a certain pressure they “THINK” 🤔 they should achieve.

[@ThunderbirdRocket]

Super helpful ! Extraordinary detail !! I learned lots !!! Thanks a lot !!

[@hillbilly3366]

Great job. I like learning new things.

[@Okie-Tom]

I appreciate this video. Anxious to watch more!

[@djosbun]

Excited for part two!

[@DuanesDiagnostics]

Very good info! You explain and teach it very well! Very helpful....especially the info about using the thermometer temperatures. Love all your videos!

[@GUE5TPA55]

Can't wait to see the next video in this series....

[@user-te3pn4pb4u]

me too, i want to see if he gets real deep into this, cause we all have been doing bad things to the ac system because we were not taught the right way, also check out tom lech ac, he has made me do a 360 on this stuff. also look up ac micron gauge that will really up your game

[@method408]

Great video, thank you love the lesson

[@danielgr.3006]

I love this! Is part 2 coming any time soon?🙈

[@Ronsas98]

I will definitely be sharing this to my techs. I tend to over explain things. Can’t wait till the next video comes out. Way to many times mechanics throw the parts cannon at a/c repairs.. thanks Sherwood

[@ryan.mullen]

Such a great video. I really appreciate this. AC is definitely not my strong suit. This series will definitely help me a ton.

[@Mr2004MCSS]

Very nice explanation of how the system works. I really liked the explanation of what temperature difference to look for at the condenser and evaporator. I will definitely use that information in the future. I will mention that not all orifice tubes are near the evaporator. The OT on my 98 Chevy trucks is right off of the condenser in the line right behind the passenger side turn signal lamp assembly.

[@davidjackson4112]

Sherwood, many years ago, I read that an ac job is the removal of heat or absent of heat.

[@CodycoWeb]

Yep there is no such thing as cold only absence of heat.

[@faheemraqib1035]

What happened to the series I was anticipating some good lessons.

[@michaelt8330]

It would be really easy to show the cooling properties of all the components with a thermal imager on a orifice tube system. Just a thought.

[@jeffireland5672]

In your upcoming series please help me further understand where the state of matter changes, of course you explained the metering device, however I get confused at times which side or part of the system can have high and low pressure liquid and gas. Thank you for sharing your knowledge

[@ky8465]

The high side is liquid freon, as liquid passes through the orifice tube it evaporates inside the evaporator turning into a gas. Evaporation is a process that removes the heat.

[@martinarrieta248]

Grasias

[@HyperSlayer72]

Bring on Part 2!

[@terryjordan8930]

When will part 2 happen?

[@tluperz400]

One thing I’ll add is everyone has their own opinion on blower fan speed while checking for the 5° difference on the evaporator. What do you recommend on blower speed?

[@CodycoWeb]

Lowest setting. Will give truer evap temp as the air passes slower across evap and can absorb more heat.

[@tluperz400]

⁠@@CodycoWebthat’s what I have always used. But some training classes I’ve been to has been mixed feelings depending on instructor. I was curious what Sherwoods opinion was.

[@CodycoWeb]

Also more than 5 deg means the evaporator is filling all the way up. It is still changing state from liquid to gas in the evaporator. Think of it like a propane tank half full the frost line equals the fill volume. You want the evap 100% full but not overfilled.

[@DrennanBuiltRacing]

when will part 2 be available

[@khasem87]

i'm confused about the accumulator , is it the same as filter dryer or not , because accumulator normally describes a device to store excess liquid refrigerant to prevent liquid from going to compressor . please help

[@user-te3pn4pb4u]

their is a desiccant bag in it for moisture control and a screen . if you can find one cut it apart, i cut and disassemble lots of things it gives you more understanding of how they work. cut the end off a newer style condenser, you will see that the condenser has become a filter. experiment, learn and never stop learning get or look up micron gauge . most shops including dealers dont use them

[@CodycoWeb]

Yes due to using a fixed orifice tube the change of state in the evaporator is not adjustable so they use accumulators to ensure that no liquid can reach the compressor. It has desiccant bag in it to absorb any moisture. It works the same way as a filter/dryer except it does prevent liquid from entering the compressor. I’m sure he will cover that in next part/parts..

[@nickayivor8432]

Can't wait for next video Brilliant thanks for sharing it 👍 SHREWD Royalty Auto Service From Nick Ayivor from London England UK 🇬🇧 ⏰️ 23:18pm

[@edforthewin8574]

I don’t care what chemical engineers got to say about your awesome explanation on how the A/C system works Mr. Royalty! Thank you so much on helping us to better understand this subject!😁

[@jeffmiller6100]

Please remember High pressure Gas .. Low pressure Liquid.

[@CodycoWeb]

Not really the system uses high and low pressure gas and high and low pressure liquid. Refrigerant is low pressure gas from evaporator to compressor and high pressure gas from compressor to condenser. State change occurs in condenser from high pressure gas to high pressure liquid thus releasing heat energy. Opposite occurs in evaporator.

[@1uniquez]

Where is part 2, etc ?

[@bartscave]

Thanks for this series! I hate it when teachers try to explain how evaporators suck heat out of car instead of simply being cold and blowing air through it.

[@user-hi3pt3mv2i]

not trying to knock you but its liquid coming to the orifice not a gas. and you have to use lab grade c02 for that testing but thats another subject. and the drier part comes back to how dry you got the system before you charge it. if you pull down to 500 micron and then cut the vacuum and it does not rise above 1000 micron which is the standard for hvac,you will have a dry system. i hope you will do a more professional video after this one

[@H8HotWeather]

9 months later and no part 2?

[@user-hi3pt3mv2i]

also i no you are under the gun here .iwould not have used the numbers u used for that 20 to 50 degree difference . the coldest that will come out cant be lower than ambient in front of condenser coming in, hot travels to cold is correct. 20 to 50 is a rule of thumb and we no how that goes, does not apply all the time