Fast Check for a Very Low Refrigerant Charge on an A/C Unit!

[@acservicetechchannel]

My Paperback, E-Book, Workbook, Quick Reference Cards: www.acservicetech.com/store E-Book: play.google.com/store and search "AC Service Tech" My Paperback and Quick Cards: www.amazon.com/shop/acservicetech Support the Channel: www.patreon.com/acservicetech Tool List: www.amazon.com/shop/acservicetech Follow and Like our page on Facebook to get unique content and updates posted every other day!! facebook.com/acservicetech Related Videos: Saturated Temp Basics, P/T Chart, Reading the Gauge Set: kzbin.info/www/bejne/fHzceKh-gLqBptE Total Superheat Method for Fixed Orifices: kzbin.info/www/bejne/qWqsYpSMqsyXobs Finding a Refrigerant Leak with an Ultrasonic Leak Detector: kzbin.info/www/bejne/nmeTqpSqp9OohsU Easy and Quick Way to Check A/C Refrigerant Charge: kzbin.info/www/bejne/m3rCn5h3j9B-j9k Checking the Charge Tools: Yellow Jacket Refrigerant Gauge Set amzn.to/2aenwTq Refrigerant hoses with valves amzn.to/2aBumVI Yellow Jacket Gauge set & hoses amzn.to/2vLVkV9 Yellow Jacket 4 Port Manifold w Hoses amzn.to/2BkuGIq Digital Refrigerant Scale amzn.to/2b9oXYl Ratcheting Service Wrench amzn.to/2dGV4Nh FieldpieceSMAN360 Digital Manifold Set amzn.to/2BdoaD4 FieldpieceSMAN460 Digital Manifold Set amzn.to/2nB4Fe6 Compact Ball Valve for Refrigerant Hose amzn.to/2KUisW8 QuickDisconnect 90 for refrigerant hose amzn.to/2MMtVcg RectorSeal Bubble Gas Leak Detector amzn.to/2ckWACn Fieldpiece ST4 Dual Temp Meter amzn.to/2wc1ME3 Fieldpiece Bead K Type Temp Sensor amzn.to/2DBwKfs Fieldpiece Wet Bulb Temp Sensor amzn.to/2RRI7Tw Fieldpiece TC24 Temp Clamp amzn.to/2qHLyjZ Electrical Diagnosis Tools: UEI DL389 Multimeter amzn.to/2xAdaJf UEI DL479 Multimeter with temp sensor amzn.to/2jtsUbJ Magnet Jumpers- amzn.to/2PyKPQZ Alligator Jumpers- amzn.to/2PxqJXn Irwin Wire Stripper/Cutter/Crimper amzn.to/2dGTj2V Vacuum Tools: JB 6 CFM Vacuum Pump - amzn.to/2nqbvo8 CPS 4 CFM Vacuum Pump - amzn.to/2DxgPwY 1/4" Appion Valve Core Removal Tool - amzn.to/2uYr8WL 5/16" Appion Valve Core Removal Tool - amzn.to/2JHmfbP Appion Blue 3/8" to 1/4" Vacuum Hose - amzn.to/2uYlVyc Appion Red 3/8" to 1/4" Vacuum Hose - amzn.to/2uYg6Ro Yellow Jacket 1/4" by 1/4" 3’ hose - amzn.to/2umtcod Appion 1/4" by 1/4" and 3/8” hose - amzn.to/2Zyxzx9 Uniweld 1/4" by 1/4" 2’ hose - amzn.to/2GFov1Y CPS Vacuum Micron Gauge - amzn.to/2v1nM3O JB Vacuum Pump Oil - amzn.to/2mGrlXy Flaring Tools: Yellow Jacket Flaring Tool - amzn.to/2OBxGlM Spin Flaring Bits 1/4", 3/8", 1/2", 5/8", 3/4"- amzn.to/31BCs8Z Yellow Jacket Flaring Tool with Set Depth - amzn.to/2QIKsQH Yellow Jacket Torque Wrench - amzn.to/2NRR68Q Uniweld Swage and Flare Kit- amzn.to/2T55jyn Nylog - amzn.to/2MLJcch Ridgid Tubing Cutter - amzn.to/2DnjjR1 Wolverine Tube Reamer - amzn.to/2QGLyMV Swaging Tools: Manual Copper Tube Swage/Expander- amzn.to/2WRPa1M Spin Swaging Bits 1/4" to 7/8" for the Drill- amzn.to/2YQwwqS Uniweld Hydraulic Swaging Tool- amzn.to/2MlrI8m Uniweld Swage and Flare Kit- amzn.to/2T55jyn Uniweld Hammer Swage kit- amzn.to/2CzWMMU Uniweld 3/4" Hammer Swage- amzn.to/2CzXsSs Uniweld 7/8" Hammer Swage- amzn.to/2Mja5WE Uniweld Multi-Size Hammer Swage- amzn.to/2T3Cx1b Brazing Tools: Air Acetylene Torch setup - amzn.to/2aQalsb 15% Silver Brazing Rods - amzn.to/2gVLyLc Ameriflame Oxy Acetylene Torch Setup #1 &#2 Tip - amzn.to/2SRm3JF 40cu B Tank to 10cu MC Tank Acetylene Tank Fitting - amzn.to/2GxZZPi Nitrogen Regulator - amzn.to/2bXdR5f Uniweld NitroVue Flow Regulator - amzn.to/2GnsaAo Uniweld Nitrogen Flow Meter - amzn.to/2brvoBg Stay Brite #8 Silver Bearing Solder and Flux - amzn.to/2XIDJsY Aluminum Braze Rods - amzn.to/2IGNMu Refrigerant Leak Detection Tool: Accutrak VPE Ultrasonic Leak Detector amzn.to/2nFYKVe Shop through Amazon! Your Purchases through Amazon provide a means for channels such as mine to earn advertising fees from all purchases after clicking through. Prices are the same as normal.

[@coolramone]

Wow this video is like on another level IMO. Thanks Craig.

[@borshardsd]

These videos are aging like wine. Sorry, I am 3 years late, but still appreciate the information and delivery. Well done ac service tech team.

[@MaMa-qh4dy]

Direct to the point with no fluff. Thanks Greg. Much appreciated! And folks, GET THE BOOK! You will be glad you did!!!

[@acservicetechchannel]

Thanks a lot Ma Ma! I really appreciate you taking the time to write that!

[@kevinfrawley6098]

I appreciate you being so thorough with everything you teach. I just bought your workbook. I went to school to get my epa universal and achieved that. I've learned more from you then many others

[@acservicetechchannel]

I really appreciate you taking the time to let me know, thanks!

[@rmeken]

You are the best in teaching HVAC on the web thanks for info

[@acservicetechchannel]

Thanks a lot Ken!

[@dylandrymond3951]

I learn something new every day. Thanks craig.

[@acservicetechchannel]

Glad to help Dylan!!

[@acservicetechchannel]

Special Thanks to Brandon for all the editing and design changes to make this video possible! We are now on Facebook! facebook.com/acservicetech Follow and Like our page on Facebook to get unique content and updates posted every other day!!

[@theairconditioningguy]

Love how simple to understand you made this video.

[@acservicetechchannel]

Glad you think so!

[@Froggability]

Looks good. The only thing I do above this, is an additional ball valve that would fit between vac gauge and machine port. The purpose being to do an immediate pump and gauge test within the first couple of minutes. I get to see my gauge drop right below 50 or even 20 micron. Not just 500. Helps test the hoses for leaks also

[@chriscermak3188]

Excellent Craig. Love the graphics.

[@acservicetechchannel]

Thanks a lot Chris!

[@izzymoney85]

Nice video love to show this to our new rookie who's just started not to long ago 👍🙏😎

[@acservicetechchannel]

Awesome, thanks!

[@ronwalker2887]

Another great video with tons of great information. Thanks very much!

[@acservicetechchannel]

Thanks a lot Ron!

[@shine-cg9uf]

If there is a restriction in the system n the unit is off what pressures would u read on hi n lo sides ? I thought if there was a restriction n the unit was off then the static pressure would b low n not reach ambient temp. This is for commercial refrigeration units like walkin n reachin coolers/freezers.

[@BlueCollarBiceps]

Thank you, this is very straightforward and understandable

[@acservicetechchannel]

Glad to help Blue-Collar Biceps!!

[@kwt298]

This guy is great with really great information but everything he does is on Split units. I wish he would talk more about package units.

[@_rx7224]

Does this also apply to package units, walk ins and reach in coolers and freezers?

[@coldfinger459sub0]

That’s why I have owned a refrigerant identifier since 1994 you would not believe how much contaminated refrigerant there is out there either mixed with other refrigerants or high percentages of air.

[@acservicetechchannel]

Awesome! thanks T lech!

[@jimedwards1307]

Nice to inform techs about the non running pressure check. But it's not "air" freezing on the coil at 32F. Also, I tell my trainees that it should be between outdoor and attic (if it's in the attic) temp as they are usually not the same. Thanks, though!

[@acservicetechchannel]

Yes I mean't the humidity in the air, and yes its not usually the perfect scenario. I just wanted to get the principles in their minds, thanks!

[@iennguyenhungphat97]

I like video for you. It helps me to understand more knowledge.

[@acservicetechchannel]

Glad it helped!

[@valcao9844]

Thanks for the info Craig! Quick question though, if indoor temperature is a different temperature than outdoor temperature, how much of a difference will that vary the pressure to temperature correlation? So for example i put my thermometer on the outdoor unit and measured 70F outdoor ambient temperature but indoor temperature is say 73F, will this effect pressure temperature measurement? And is there a say a range +/-5 degrees? Thank you for your time!

[@BigdaddyJulian]

So when checking charge with the system off assuming outside temperature is 85 and inside temperature is 72 does that mean I’m looking for 78.5 saturation equalized pressures at my gauges?for a charged system?

[@acservicetechchannel]

It will more closely match the outside temperature and it will depend on how long the outdoor temp has been that high for. So to put it into a real world situation, when I walk up to a system thats very low on refrigerant and off and equalized, when I read a sat temp on both gauges lower than what the indoor temp is, I know somethings wrong because the indoor temp is usually lower than the outdoor temp. Either the wrong refrigerant is in the system or more likely, it has lost all the liquid and there is only vapor left. Thanks a great question!

[@Froggability]

If it seems close to normal the only way to tell is by running the machine. That's because you can lose over 3/4 of your gas and static /resting pressure remains the same. On cooling low pressure will drop like a stone

[@michaelcostello6991]

6.85 Lb factory charge in your video. How much tolerance is there on the amount of charge for system to work properly. Thanks

[@Achabab]

Is It your book teach how to check the gas for the air-con, inverter systems, 1 compressor can use for 2 unit,3units,4units.... Because her in Singapore all ppl use system inverter, and the air-con have just LP for you can top up the gas. I already see the video for Mitsubishi inverter, but they dont show the details

[@jasonhoyt8232]

Do you have a book which prepared on to take the 608 Certification test? If not, will you please write one? Your book is second to none.

[@acservicetechchannel]

I don't at this point yet but I would like to do so in the future, thanks!

[@jasonhoyt8232]

@@acservicetechchannel When you do write it, will you please make sure to use the glossy pages exactly like you did for the other book? It helps a lot with durability and readability. I'd rather pay an extra $20 for that type of paper.

[@GNC2760]

Hi, Mister Craig my name is Nelson. I was checking an r-22 heat pump system with txv in the air handler. I used the subcooling method 250 psig, 91F temp.t1 the first time. I added the inf to the measure quick app with an 11target subcooling, cause I couldnt read the data plate and the app said that I had to remove refrigerant. However, the blue gauge showed the saturated temp. between 32, 33. also, I measured Delta T and it was 47. something on supply and 71 on the return, but 24 is higher than 18-21. So, my question is if Can I remove refrigerant from the system with the blue gauge on that number?

[@michaelcostello6991]

How much refrigerant pressure must still be in the system to do a proper pressure test ?? on low and high side. Would you add a little refrigerant for the test etc etc Thanks

[@robertl.7657]

Good video, keep the good work, would you do videos on checking components on certain scenarios, to troubleshoot!👍

[@acservicetechchannel]

Robert, I would like to in the future, thanks!

[@Shutyourjibbs]

Does this work with geothermal systems also?

[@marcusdarnell3348]

Thanks Craig! on point as always lol!

[@acservicetechchannel]

Glad you enjoyed it Marcus!

[@JoseGuerrero-sj5ie]

Another great video sr thank

[@acservicetechchannel]

Thanks Jose!

[@ralphgiampietro85]

How are you figuring an iced up coil low on refrigerant due to low subcooling where the coil is totally iced over that uses a fixed metering device tev yes understood but a fixed metering device goes against what I have read and told by many

[@acservicetechchannel]

We check the charge with subcooling on systems that have a txv and systems with a fixed orifice with total superheat. However, even if an evap coil is frozen over with a fixed orifice, a system will still have some subcooling. If the subcooling is only 1 degree while the coil is frozen, then the system is going to read as low on refrigerant when checking with total superheat after you defrosted the coil. If it had say 5 degrees or higher while the coil was frozen, it could go either way and you could melt the coil to tell and check with superheat.

[@christianbacon7027]

Thank you for ur videos!!

[@acservicetechchannel]

Glad to help Christian!

[@pizzle1011]

Good content! Thanks 👍🏾

[@acservicetechchannel]

Thanks piz11!

[@tyebundlez8262]

Your the best for this one thanx a lot

[@acservicetechchannel]

Glad to help

[@jamarknight6679]

Do this work for micro channel coils

[@acservicetechchannel]

It would be very similar on this scenario yes as long as the system had a single or two speed compressor running in second speed, thanks

[@coling9803]

Need to get this book in Canada but over $50 shipping is a killer

[@acservicetechchannel]

Colin, I apologize for the shipping price to Canada but there just doesn't seem to be anything we can do about the price to get it over the border there at this present time, especially with Covid and trying to maintain fast shipping times. There are bundles available on the website at www.acservicetech.com/store that include fast shipping. We also have the ebook available on our website and on google play that is less expensive, thanks!

[@KendallVance]

at ~1:00 "Saturated Temp should match surrounding air temp". Lost me here. Why should sat. temp = air temp when system is off? (I watched the sat Temp basics, but did not see this point addressed).

[@tamershata4640]

I specialize in air conditioning and cold rooms

[@YTsux24-7]

Mic drop knowledge bomb.

[@acservicetechchannel]

Glad you enjoyed it Tom! Thanks for your support!!!

[@gktech7751]

Wow really Good job

[@acservicetechchannel]

Thanks a lot GK Tech!

[@bryanmania888]

Hi ac service tech :) im a fan of yours from the Philippines. Im more of a diyer and been researching about the problem of my 2 horsepower mini split AC (LG HS-18ipm inverter ac model number) Can i ask about your opinion on what may be the problem of my AC system? Thanks I am experiencing icing of my evaporator everytime my condenser (outdoor unit) gets a THOROUGH cleaning (i installed a watt meter on my ac and when the consumption hits 1,100 watts ice slowly forms on the evaporator). Icing happens when i set the thermostat to 24 degrees celscius or below BUT here is the contradicting problem. When for example my condenser or outdoor unit hasnt been cleaned for like 4 to 5 months it is very dirty and almost clogged, BUT, i dont experience any icing on my evaporator (indoor unit) and cooling is excellent and working fine, i can even set the thermostat to 18 degrees without icing (consumption on the wattmeter registers 2100 watts) What could be the problem? The ac technician who handles my AC servicing couldnt give me a clear answer. Hoping to hear from you soon. Thank you! Godbless

[@JDT738126]

Great video

[@acservicetechchannel]

Glad to help!

[@deanmartin1966]

Great info

[@acservicetechchannel]

Thanks Dean!

[@deanmartin1966]

@@acservicetechchannel Just ordered your book. Too much good info to miss out. Thanks

[@acservicetechchannel]

Awesome, thanks Dean Martin and please let me know what you think of the book after reading it!

[@MrChipBryant]

Thank you.

[@acservicetechchannel]

Glad to help Chip!

[@Gameboy_Steve]

Awesome thank you

[@acservicetechchannel]

Glad you enjoyed it!

[@f.oliveiraclimatizacaoeele1286]

Boa explicação Vamos disseminar as informações para o mundo Aki é do Sp, Brasil 😉

[@acservicetechchannel]

Estou feliz que você apreciou o vídeo!

[@WillieMakeit]

trust me people get the book

[@acservicetechchannel]

Thank you very much Willie! I appreciate it!

[@2K5W9M1]

Subcooling can be used on an orifice to tell me if the charge is off?!?!

[@acservicetechchannel]

Not exactly and no you cannot measure the charge with the subcooling method with fixed orifices. However, in the event of an evap coil that is fully frozen, if the subcooling is between 7 to 15 degrees, this tells you that you are not severley undercharged with refrigerant. Thats all. Its just a quick method to know whats going on. If subcooling was 0 degrees with a frozen evaporator, you would know that the system is undercharged.

[@INTERNA9]

Thanx

[@danielrocha2890]

First of all let me tell you that you really know your stuff and Thank you for all the videos and good information. Now a constructive criticism in my opinion you talk to fast and try to jam to much info by repeating to much .

[@mustafaabdulameer9450]

How to get the book

[@acservicetechchannel]

You can purchase it through our website at www.acservicetech.com/ac-book or through www.amazon.com/shop/acservicetech and the E-book is available at google pay store and our website, thanks for your interest!

[@bobmartin4016]

I recently got back into HVAC (after being a Electronics, radar, power generation and high voltage experience). My new HVAC mentor instructed me to check the HP saturated pressure, then check my app and add 30 degrees to the ambient outdoor temp to the app to get the applicable super heat refrigerant pressure to determine if the system is low or high on charge. I have found this is bad idea, heat every HVAC tech I have met uses this method. WTF?

[@acservicetechchannel]

That is such a shame. If they would only read some manufacturer install literature, they would know how to properly charge refrigerant. Crazy!

[@mikefreedom5612]

First tip is incorrect, in refrigeration 10g or 1kg of same refrigeration at equilibrium has same pressure, doesn't matter the weight. Please correct that in your slide

[@acservicetechchannel]

Immigration Freedom. The pressure would remain the same in a system or bottle as long as the refrigerant still had some liquid left regardless of the weight. If it has liquid and vapor present, that is saturated. However, I am explaining when so much refrigerant leaks out that there is only vapor left, the pressure will be lower. Due to the availability of space in the tubing I often find about 7/8 or more of the full refrigerant charge has leaked out. If the charge had only leaked a little bit, the pressure in the system would have remained the same because there is still liquid in the saturated mix. This is an odd scenario that no one seems to talk about so I thought I would throw it out there. Check out the other video on saturated temperatures. The link is in the description section of this video, thanks!

[@mustafaabdulameer9450]

Please I am from Iraq. Can you help me? I want to write what you say with the comment. Then I am translating it

[@acservicetechchannel]

Are you saying you are translating what I am saying in the video or are you trying to ask a question in the comment section?

[@charlesbelanger3105]

B7

[@bobgallo2178]

Keep in mind, this IS NOT for the average d I y guy. You need to have some formal training before attacking a refrigeration issue. Also must be certified to handle refrigerants.

[@acservicetechchannel]

Absolutely, you must be EPA 608 certified before handling any refrigerants. These HVACR training videos are primarily focused toward those in HVACR school and those in the HVACR and maintenance trades, thanks!

[@3beltwesty]

Well before say 1990 it was simply the average person's simple easy task. Ie folks topped off ac units in cars in window units and central air units. There were not even any recovery units or recovery tanks then. A 30 lb jug of R22 was 25 dollars at the local NAPA store. In Window units the bigger ones came with instructions on how to add refrigerant. Maybe in 30 years one will need an EPA license to change the oil in a mower since regulated? :) Pre EPA refrigerant rules the 30 LB jugs of R22 or R12 etc were two way valves. Ie one could pump back good R22 into a used R22 tank to reuse the Refrigerant after doing repair. Later the valves hit changed so one cannot do this with an old tank. Pre say 1990 EPA rules the common then R12 12oz and 14oz cans were used for air horns on boats and for ball games. Also for toys that shot BBs. Eons ago the cans were 50 cents each when gasoline was 33 cents. In automobiles an ac unit can just have a slow leak in seal in the compressor. Using it every month helps keep the seal healthy

[@bobgallo2178]

@@3beltwesty Yep, those were the good old days. Things have changed, leave it to the professional. Note, I am retiring soon.

[@theairconditioningguy]

You need to open a trade school.

[@tamershata4640]

Can I find a job