In this video, I'll be pulling a vacuum with a vacuum gauge and a micron gauge. We'll compare our results and I'll answer some questions throughout the video that were most asked when I did the mini-split series. Enjoy the video!
I can only imagine how many people get ripped off by hiring the wrong ac tech to work on their cooling systems without the proper equipment, procedures and knowledge. Your video is spot on. Thank You.
You are correct Tom that there are a lot of tech who will do a job without the correct equipment, knowledge and will charge top dollar for their services. Thanks for watching and leaving a comment!
After watching this video, I now know that I got ripped off. I watched the local tech charge my heat pump. I remember thinking "wow thats all it took, 15 minutes". Now I know the 30 or 40 minutes of work that he should have done but didn't do. 3 years later and several months out of warranty, Boy don't wish now that I had recorded him.
Wow, from a beginner's learning point of view, this was an excellent learning video. Thank you for taking the time to break things down the way you did.
Absolutely fantastic presentation. The knowledge and experience is 10/10. Rarely do I click any subscribe button after viewing a single video, but in this case it's warranted. Again, excellent work. Thank you.
Terry that's a huge difference between both gauges. I'm thinking without the micron gauge you really have no idea in reality how much vacuum your at. In ac systems your drawing down at best by guessing using analog gauges. Wow thats an eye opener. Great demonstration Terry 👍
You're exactly right Steve! When you're using the vacuum gauge on a manifold set, you will never know how much air is still in the system. Thanks for dropping in and sharing your thoughts. :)
Thank you for your video I want to put mini split and was thinking save here, save here etc. you have convicted me 100 % that saving would not be a good idea, I am more or less your age and I still remember how nice mercury moves on hands, how little was not said about how poisonous it can be , one again thank you for your story not only you moved me 35 years back or so but also helped me a lot to answer all questions I had today
Thank you very much Jerry and glad that you found the video helpful! Just released a video yesterday Jerry if you're interested in a riding mower's charging system. It will be a three part video series which is all educational. Have a great day!
I'm glad I watch your video. This is the most informative one online for a DIY. So many others just use manifold gauges which I was going to also. And they believe it's accurate enough. Even some who seem to know a lot about this. I originally tried to do this job at minimal costs, but after researching a lot, I ended up buying everything I thought would be best. I did buy extra tools I didn't need, but that's OK. It was still more cost effective than hiring someone to do it for me. I was quoted 2000 thousand for labor to do the whole job. Well it only cost me 400 for misc tools including the Micron gauge you recommended, the 2 core removal tools, along with the wall kit to hide lines and a vacuum motor. Not to mention the manifold I won't need for this job. So thanks for being so descriptive. All other videos left out many details for someone who never worked on mini split units.
Good for you Bert to purchasing the tools to do the job right. And even saving yourself 1600 dollars in the process. Even though you were quoted 2000 dollars, it's still not a guarantee that the job would have been done correctly. Sounds like you did a great job and I commend you on taking the time in doing your research. Thanks for the comment Bert and wish you continued success. 😊
@@stuzman52 All thanks is for you. It's not easy to find the right information on the net or anywhere if you don't really know the right questions to ask. The simplest thing like pushing the schrader valve back in under pressure was eliminated in all the videos I watched that you took the time to show. Even how to hook up the manifold lines weren't discussed if I were to use them, wasn't really explained. Things the laymen should know about to do this. I actually haven't done the evac yet, I'm waiting on the second core removal tool I order after watching your videos. It should be in sometime today. But the install is complete. If it gets here early enough today I will do it. I could use it now. It's going to be 98 degrees today and tomorrow. But I still have my window units where it's needed most. lol
Wow ! That was awesome ! Very informative. Terry, basically you're saying that using an analog gage is like trying to measure an atom with a tape measure ! LOL I
I never realized how inaccurate a standard vacuum gauge can be. About 30 years ago when I started working on cars a well seasoned mechanic I worked with told me to leave the vacuum pump on the ac lines for an hour. I didn't know why but I do now. 😀 Thanks for the video Terry I found it very interesting. And yes I was also one of those kids who played with mercury when the science teacher left the chemical room door open. The story you told had me laughing my ass off! 💯 I have been down that road.
Interesting Glen that you were one of those curious, mischievous students who got into stuff too! Great minds think alike! Thanks for watching and sharing a comment!
yes u have to pressure a system for leaks and some leaks are tough, but auto ac guys at dealers mind u, have no nitrogen and they never truly get ur ac dry cause they never use a micron gauge. so 30 yrs later they still dont no. crazy
Thank you SparkeyDogfish for dropping in and sharing a comment! You won't regret getting a micron gauge. It's one of the best investments when you're working with refrigeration systems. Have a great day!
Fantastic information and you explained it so well and made it easy to understand. Before this video I was confused. I will now buy a micron gauge and a bottle of nitrogen before I install the split system that I was about to install. Thank you.
Great videos. The mercury story was scary and funny at the same time. Mercury does that with gold. It readily bonds with it to form an amalgam. They use it to extract small amounts from ore because of this. I can see how it would literally dissolve their rings if they were solid gold. The only way to separate them is to heat up the amalgam to the boiling point of mercury and boil the mercury off, leaving the gold behind. Talk about a poisonous and dangerous process!! Subscribed!!
For sure it was scary at that time when you when didn't know if we had to pay for all of those rings. And looking back at it now, we were really dumb as a rock not knowing the hazards of mercury. Thanks for the comment!
Just got my tank yesterday and the regulator as well at air gas. Totally agree with what your saying. Why wouldn't I lol cause I don't know any better am a very very new rookie 😊. I follow you and the other guy. The guy who speaks really fast but have learned a lot from him too. I appreciate your honesty.
i have been watching tom lech auto motive ac channel, us mechanics are always taught wrong. you and him has taught me my evil ways, im repenting every day. i love smart people to learn from thanks for you and him
very informative, thankyou for the video. i learned something new today. i am working on a ford shuttle bus with front and rear ac. replaced condenser, discharge line, expansion valve for the rear, orifice tube for the front and the drier, put it under vacuum for about an hour and then recharged. now it the problem is that the inlet to both evaporators freezes and the outlets are hot. at first i thought the evaporators are clogged. but now after seeing this video i come to a new theory, that there is moisture in the system still causing the freezing. because of the freezing the high side of the system has a higher pressure reading.
The next time I have my air conditioner serviced I'll be watching the guy to see if he knows what he's doing. I sure learned something about the difference between the R-135 gauge and the micron gauge. May I assume most auto shops only rely on the R-135 pressure/vacuum gauge? I've never seen my local guy use nitrogen or did he have a micron gauge.
wyattoneable Glad to heat that you found the video useful Wyatt! In the EPA 609 guidelines, it’s a requirement to have a system pumped down to at least 500 microns. Section 609 includes residential, commercial and industrial units. Automotive falls under section 608 which doesn’t require a micron gauge and you’ll see the typical manifold gauges used. Even the recovery machines use analog gauges for evacuation. For me, I’ve starting using a micron gauge on automotive systems. Great question Wyatt and thanks for the comment.
You make a good case for why vacuum test can't be used instead of a pressure test. You explain that is because the analog gauges have low resolution and you wouldn't be able to see a tiny leak. But we know a micron gauge has way higher resolution. Would it be ok to rely on a vacuum decay test with a micron gauge to detect tiny leaks?
It takes a while to wrap one's head around why evacuation takes so long. The first thing that occurs is the maximum pressure gradient driving molecules, never more than 14.7psi. This is in contrast with filling, where a pressure difference can be hundreds of psi. The second factor is the way water will cool as vacuum is applied, resulting in condensation and even ice forming in tubing. Pumping air, we need to give it time to sublimate or boil back to a gas before water has any chance to leave the system. All of that takes time. Terry, I haven't seen any repair videos from you in several months. Hopefully all is going well, ha ha.
Leaving the dream Dave 😊! Actually, I'm doing some filming on a project now and taking my time with it. Not quite sure when I'll be ready, but hopefully it will be educational.
Can i substitute the micron gauge adapter with a hose (hose from valve core removal tool to the gauge)? My gauge only has a male fitting and it didn't come with an adapter. I already have a hose and $30 for a small adapter seems like a ripoff.
Thank you sir. You answered all of my questions except which cheap micron gauge one is the best. LOL. All the reviews I see for some of these gauges are bad. I think its because people keep getting oil on the sensor and not cleaning it. I went to try and get the Bluevac Micro but they are sold out so I am going to have to find a cheaper alternative.
Glad to hear that you liked the videos. I haven't any experience with any of the other alternatives and some of the reviews are bad such as the unit leaking. It could be as you said that the gauge may get contaminated by the refrigerant oil. That's another reason I use an isolation valve which I forgot to mention in the video. I know a professional tech who uses this gauge in his RU-vid videos and talks highly of it. It's located here: www.amazon.com/gp/product/B009AXGCSC?pf_rd_r=7A8NN4SHWJZYKCGBDXJP&pf_rd_p=edaba0ee-c2fe-4124-9f5d-b31d6b1bfbee For my gauge and other items, I use this site. www.trutechtools.com/ I had to wait a week or so for the micron gauge shown in the videos to arrive. There are cheaper alternatives as you mentioned, but I haven't used them. According to the website, the BluVac micron gauge should be in stock within 5 to 10 days. If you're not in a hurry, it's located here: www.trutechtools.com/Accutools-BluVac-Plus-Micro-Wireless-Digital-Micron-Gauge Good luck on your projects!
@@stuzman52 I was going to order from truetechtools because I'm a member of HVACTalk but when I asked how long they had been out of stock they couldn't say and they also mentioned it could be an issue with the manufacturer not having enough parts to build them. So I found a Fieldpiece SVG-3 to use instead.
Deneteus Sorry to heat that, but Fieldpiece makes excellent products also. I’m sure that you’ll be happy with your purchase. Best wishes with all of your projects.
I'm about to install a Pioneer 12k mini-split and I'm trying to use what I have. What I have is a vacuum pump with automotive gauge manifold. My plan was to pull a vacuum for an hour or so then see if it leaks down. Then pull a 2nd hard vacuum before releasing the refrigerant. I plan to use the flare seals that came with the unit and nylog. Any advice for a newb to hvac without fancy tools and no money to call a pro?
Hi Mike. Sure you can do what you've got planned. Just keep in mind that if you have a very small leak, you may not be able to pick it up with your gauges. That's the reason for the nitrogen pressure test. Good luck with your installation and have a great day!
As you point out with so many variables involved, pulling a vacuum for an arbitrary duration makes little sense. I certainly picked up a couple of points, I had not considered. Thx & cheers 👍
Hi Ian and Happy Father's Day! Yes, pulling on different volumes of air with different systems is impossible to know how long a vacuum pump should run. Have a great Sunday!
The mechanical analog gauge showed correctly. It just the human eye couldnt pick up the micro movement. What if the electronic senor was damaged? You get incorrect measurement thinking its correct but its not. It a combination of all the tools to determine the correct reading
Why is it when you hook up the micron gauge directly to the vacuum pump with a shutoff valve (core tool remover tool), pull the vacuum and then close it off that the vacuum rises really quick? I notice if a larger volume is vacuumed like the recovery tank or lineset that the rise is much smaller and stable.
That is an excellent question proxybox and I had mentioned it in one of my videos of where I pulled a vacuum on my mini-split. I even posted a link to another channel where TruTech demonstrates of why this happens. I can tell you in this post of why this happens, but will let you watch the video as there is some other good useful information. Here is the link to the video and the explanation to your question is on the timeline of around 5 minutes into the video. Have a great day! ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-cI6pSBaskjc.html
Wow thanks! I've been looking for a definitive answer this phenomenon. I thought that my core tool was bad but now I know how to properly test the setup. Much appreciated!
Great video! I am going to install a mini split soon. The micron gauge you used is great but expensive. Can you recommend a micron gauge that is less money?
Here is a unit from CPS which is about $130. www.amazon.com/CPS-VG200-Vacuum-Digital-Display/dp/B009AXGCSC/ref=sr_1_4?hvadid=78271554844691&hvbmt=bb&hvdev=c&hvqmt=b&keywords=micron+gauge&qid=1581267429&sr=8-4
remember all your fittings have to be rated for 20 microns or so otherwise as soon as you pull your vacuum and start your decay test the numbers will easily rise above 500 microns.
I have a dumb question - can you use the nitrogen that ships with the recovery tank to do a pressure test on a new lineset if the tank hasn't been opened yet?
Terry(?) Really appreciate your videos but I have a real conundrum: I bought a Robinair 15500 1/2 hp 35um capable vacuum pump. I have 2 gauge sets and a vacuum gauge on a hand pump unit. When I tested the pump, all of the gauges read approximately 25.5”hg. When I looked at a chart showing maximum vacuum vs altitude, these readings matched well with chart for my 4700 ft altitude of my city. So, I purchased a CPS VG200 micrometer because of your video understanding the need for low-vacuum accuracy when doing refrigeration. However, when I put the CPS micrometer directly on my vacuum-pump, it goes clear down to 4um and a reading of 29.919”hg, which is way off from the other 3 gauges (which by the way will hold a vacuum overnight so they should be good for a direct-connect to the pump) and seem impossible given the vacuum vs altitude chart. So what is going on, what is the deal with the altitude-chart, is the CPS micrometer defective giving such near-perfect vacuum readings; should I send it back as bad? Really stumped! Thanks for any help you can offer. 😀
From your discussion of your readings, it would appear that the micrometer is a little off, but maybe there something that you and I don't see. I would call the manufacturer or distributor and ask them the question and see what they say before returning it. Have a great day!
There's always a possibility that pressure from the outside could enter the vacuumed system. Standard practice is to have the refrigerant in the system and then insert the valve core. This wouldn't create a problem with a system that is vacuumed.
Hi Phil! I just checked my records to see if I kept the file. Sorry, but I must have deleted it when the videos were finished. I remembered that it didn't take too much time to create. I just took the conversions between the units and put them in the first row and then just copied them down. Have a great weekend!
Technically, it sounds like this would be true. I can remember doing two jobs where each system held a vacuum for 24 hours and the gauge didn't budge at all. However, this was using the vacuum analog gauge and not a micron gauge. So, after filling the system with refrigerant, one system had low refrigerant in a month and the other system had low refrigerant in two months. So, both systems had an extremely low leak which didn't show up under vacuum. Therefore, it's always best to test a system under higher pressure with an inert gas such as nitrogen. This would show even the smallest leaks which wouldn't show up under a vacuum. And what if the micron gauge did show a leak? You would still have to use a pressure test to find the leak. Thanks for the question and hope you have a great day!
Since I found poor reviews on all the digital micron gauges at Amazon, I looked at trutechtools for BluVac guages. For my home use I'll be getting an AccuTools BluVac+ Micro Wireless Digital Micron Gauge with Coupler and Bluetooth, for $210 + taxes & S & H. It will take close to $1000 in equipment before I can begin to do the job right on my 2004 Intrepid, while all the replacement parts are under $200.
@@stuzman52 After more study of youtube and testing of my Intrepid, I've realized that I do not need to spend $600 on a refrigerant recycling system and associated 30 lb can of nitrogen. I can have a shop evacuate the system for much cheaper. All I'm really going to need for my repair is a vacuum pump. I've already got the kitchen scale that will do for weighing the can of less than 2 lb. Realize, please, I am not fishing for coaching from you. I still intend to get the micron gauge because all the goobers on youtube telling me to run the vacuum pump for 30 minutes or 45 or maybe even overnight leave me with no awareness of remaining tiny leaks. This particular car has been in the dealer shop for various AC issues 3 different times. There has been a lot of internet hate for the Intrepid, but in the case of my AC system, I don't believe Dodge deserves the hate. I believe that the goober in the shop isn't supplied with a functioning micron gauge.
When explaining a major failure like water in a system and why the cost is what it is. Try explaining Triple Evacuation and watch their eyes roll in disbelief.
If you're hooking up the micron gauge up near the pump to check the pump is fine. But if you're evacuating the system, it's best to have the micron gauge as far from the pump as possible.
spelunkerd CO2 should be fine Dave as there is a company that uses this gas. They have a product called bull’s eye leak detector to find very small leaks. More info can be found here www.aeswave.com/BULLSEYE-Leak-Detector-Pro-Kit-p9235.html
Not sure what your question is. If you're asking what percentage of air a vacuum pump can remove, you can get that from the specifications of the pump. Have a great day!
@@stuzman52 Hi, was not a question. You use a wrong terminology. Vaccum cant by removed. you not remove vacuum from a closed chambre. you remove gas. when you reach anegative pressure you a in vacuum state. the title from your excel is not correct.
@@stuzman52 so with the analogue gauges back then, they would never of really know that they hit 500? Or was there a separate gauge specifically for micron,? Thanks for getting back 👍 So what I'm asking is, back in the day, a certain percentage of ac was never vacced correctly, but still good enough to work.
Incredible video series. Thank you so much for doing this series. Question: Can I use argon with the proper regulator/gauge unit to do the pressure test? I know the argon is mire expensive but I have a large tank of it already. Trying to keep the number of different compressed gas cylinders at hime down. Thanks again.
please help the automotive guys. they just dont get it. take time and watch those top utube guys doing ac, it will make u pull ur hair out. when u got to a dealer or any shop for car ac good luck.
