Mini-Split Heat Pump: Vacuum Procedure Using a Micron Gauge

In this video, I'll be pulling a vacuum on a mini-split heat pump using a micron gauge. For those interested in why the micron gauge rose in pressure, here is a link that explains it further. • Attaching and Troubles...
Imperial Tubing Bender: www.amazon.com/gp/product/B00...
Bubble Leak Detector: www.amazon.com/gp/product/B00...
Nitrogen Regulator: www.amazon.com/gp/product/B00...
1/4" Core Removal Tool: www.amazon.com/gp/product/B01...
5/16" Core Removal Tool: www.amazon.com/gp/product/B00...
Hilmor Flaring Kit: www.amazon.com/gp/product/B01...
BluVac Pro Micron Gauge: spwindustrial.com/accutools-a...
Yellow Jacket Manifold Gauges: www.amazon.com/gp/product/B00...
Yellow Jacket Low Lost Refrigerant Hoses: www.amazon.com/gp/product/B00...
Thanks to everyone for watching!

[@mrtaktiks]

I follow this fella to the "T" and it is definitely worthwhile. He is exceptionally knowledgeable so much so I went as far as purchasing (or replacing inferior equipment I have had) every piece of equipment he shows in this video. Yes, it cost quite a bit for a residential DIY fanatic (me) but I like to have the right tools. Couple that with his definitive explanation and now I have a well-running Dual mini-split system and a happy wife. He has been incredibly generous with his time and is very patient in his explanations, and no I am not related to him. I have found that it is not necessary to jump around to different KZbin HVAC presentations as you will not find any better than Mr. Stuzman.

[@stuzman52]

Thank you very much Norman and the most important info that I picked up in this comment is that the wife is happy! And when you can do that, you're making lots of progress in life :)) Have a great day Norman and glad to hear that your unit is working well!

[@blackkatstudioinc8240]

*It’s: Pretty. Quiet. **Fastly.Cool** in my room. Works wellLittle of hassle to install was TOTALLY worth it. I’m loving it so far. I recommend watching the installation video and taking it slow~*

[@stuzman52]

Yep, pretty good system and thanks for the comment! Have a great day!

[@carlluck7888]

Mr Stuzman. I can't thank you enough for your mini split videos. I have watched all four and after watching I decided to install a 18Kbtu mini split heat pump myself in my garage workshop. I followed all your processes from bending and flaring the line set, torquing the flare nuts and pressure testing with nitrogen. I was able to vacuum my system down to a stable 198 microns. Using the two core removal tools proved to be good advice. The system is working great. Thank you for your expertise in showing your install process. I appreciated it very much. Thank your wife for the excellent camera work too.

[@stuzman52]

It's really great Carl to hear that you did a great job with the installation of your mini-split. I'll tell the wife about her filming and wish the best for you and your family! Have a great day!

[@douglasshackett8747]

Thank you! I've spent many hours trying to learn best practices for muni split install and line set bending/flaring etc and your videos are hands down the most informative. Somehow you manage to cover everything. Great job.

[@stuzman52]

Thank you very much Douglass and good luck on your install! Have a great day!

[@emilywhelan4471]

The design makes this AC a possible alternative to ductless DYI systems. It works great. The remote control could be more visual aid oriented like a backligh design. Is impossible to see the lcd at least for me. Easy install kzbin.infoUgkx_hHgTlzH3uk31Fe2RVS3xEbXHGaN_z5Tation. Came on time . Great comfort around the house 5 🌟 again. Follow mfg instructions for care and all and this should be the only AC you need for those of is that don't live in new homes with central AC

[@stuzman52]

Thanks Emily for the comment and have a great day!

[@wyattoneable]

That's a whole new discipline (home air conditioning) and a whole new set of tools and skills to master. Your pretty talented Terry.

[@stuzman52]

wyattoneable It’s not bad at all Wyatt, and I know that you could do the same thing with no problems. I just picked things up over the years; nothing special. 😀👍

[@douglashughes2331]

Impressive, you are a detail oriented master craftsman with a great ability to clearly explain details. Fantastic set of videos. Thank you very much.

[@stuzman52]

Thank you very much Douglas for the kind words!

[@muchmuchmore]

Great video. I was able to piece this process together a few years back when I installed one at my house, but this video perfectly explains the procedure all in one concise video.

[@stuzman52]

Scott Merrick Thank you Scott and glad you liked the video!

[@stevebates6281]

Thank you for taking the time to make this and sharing . Very informative!

[@stuzman52]

steve bates And thank you Steve for taking the time to watch the video! 😀

[@bobstockdale8777]

Excellent Instructor !!!!! Helped me do my AC install. Great Video. THANKS

[@stuzman52]

You're quite welcome Bob!

[@haywardsautomotive6156]

Nice video Terry and now you have a nice cool garage that'll make it more enjoyable to work in ...nice & cool in summer & warm in winter!

[@stuzman52]

Hayward's Automotive Thanks Bob and should be much more comfortable now. 😀

[@Badgertronix]

Great work Terry. Having nice cool air in the workshop would be a wonderful thing. Enjoy

[@stuzman52]

Badgertronix Thanks Jonathan and should be more comfortable for sure. 😀

[@1975frost]

Best mini split videos on you tube. Thank you so much for posting them. They were a great help!

[@stuzman52]

Thank you very much Patrick and glad to hear that the videos were helpful!

[@MikeKapotsy]

These videos were very informative and well put together. Valuable resource for anyone installing one of these!

[@stuzman52]

Thank you Mike for the kind words!

[@Ed-o]

I viewed the entire playlist; Mini-Split Heat Pump Install, Pressure Test and Vacuum. I wanted to thank you for the very professional, educational, and enjoyable series of videos. The subject matter, camera work, and detailed information included in the videos is first rate. I can tell that you are passionate about the projects that you tackle and way you present the information makes it easy to follow and understand. I’m currently installing a mini-split in my garage. Your videos convinced me of the importance of pressure testing with nitrogen and using a micron gauge instead of relying on the compound gauge to determine when a sufficient vacuum level had been reached. I spent more money on tools than I had planned, but It’s like they say: “The cheap comes out expensive”. Better to do it right the first time than to have to do it over. Thank again and keep up the good work!!

[@stuzman52]

Thank you Edward for the comment and glad to hear that you found the videos informative. Just trying to get information out there for viewers like yourself who wants to install their own unit. It sounds like you're way ahead of the game to do the job right. Good luck on your install.

[@OneLeggedTarantula]

Great video thanks! I followed your instructions step by step and had a perfect install.

[@stuzman52]

Thank you very much Maurice and I appreciate the comment. I apologize for the delay as KZbin did not notify me as it should have.

[@fly4fun24]

Best video on the this subject i have seen.

[@sc_marauder492]

I live in upstate SC. I sure wish you were close by! I'd hire you to install mine! Your workmanship and work ethic is top shelf! God Bless!

[@stuzman52]

Glad to hear that you found the video helpful! Be sure to have a super great day!

[@uwsome1]

Thanks to your KZbin channel I just put mine in today , Not all in one day it took me a while , its done Thanks

[@stuzman52]

Good for you Derek! Glad to hear that the videos helped you out!

[@albmarku4379]

The perfect vacuum I ever seen. Thanks for sharing sir.

[@stuzman52]

Sorry alb for the delay as KZbin did not notify me. Thank you very much for your comment!

[@carloslozano8693]

Excellent tutorial! I’m preparing for a dual zone mini-split installation. Your tutorial has confirmed my decision go acquire a micro gage to perform the mini-split vacuum.

[@stuzman52]

Good luck Carlos with your installation!

[@carloslozano8693]

I do have a couple of follow up questions. 1) I have purchased a dual zone Gree heat pump. After reviewing installation guides and on line tutorials I have concluded that given that the install will have line sets less than 25 feet, adding refrigerant will not be required.....is this correct? 2). This installation will be a swap out of an older existing mini-split. I am assuming that there will be special processes in handling the refrigerant lines and disposal of the heat pump. Is this correct?

[@jgm3796]

Great detailed series of videos! I am now ready to tackle this, just need wife's approval to buy more tools. Thank you!

[@stuzman52]

Thanks JG! I'm sure the wife will understand! Have a great day!

[@williamshaw8489]

I just wanted to thank you for the great instructional videos. I completed my first mini split install (Mitsubishi) , following your detailed steps. These are appreciated!

[@stuzman52]

Glad to help William and thanks for watching!

[@dottorb7054]

Man, you're a genius. First helped a few years ago to repair Jetta VR6 Secondary Air Injection (reused that part after soaking it... still working years later).. and the door latch repair.... and now Mini-Splits. You're the man!

[@stuzman52]

Thank you very much Dottor and glad that you found the videos helpful!

[@HVAC356]

Really? Genius? That makes me a Genius too!!

[@CockyMike911]

I watched this video about a dozen times back in 2019 while doing a $250K renovation on a early 1900, 4,200 ft2 house. I gained enough confidence to do the whole house in Mitsubishi mini-splits. Yea, I was a little nervous but I was confident enough to take the chance to save more than $26,000 over having to pay someone. That system had 3 condensers and 13 heads and the install was nearly flawless...! ( I made one bad flare) I talked to the lady I sold the house to in early 2024 and she said the system still runs PERFECT. I've now installed two more systems for family (a single head and a two zone) and I'm in the planning stage for a 3 condenser, 11 head system in another restoration project. STUZMAN... YOU ARE THE BOMB! Easy to listen to and tells you everything you need to know. Good job .

[@stuzman52]

Thank you Mike for the kind words and glad to hear that you had quite a few successful installations. Keep up the good work!

[@tc1904]

I follow several HVAC channels as I am fanatic when it comes to technical DYI information. I must say you are by far The best of the best when it comes to doing everything by the book and technically correct. My hats off to you for a museum quality installation and excellent quality video and narration.

[@stuzman52]

Thank you very much T C! I appreciate it!

[@nsudatta-roy8154]

Humm! This is the first video I've watched. You did a fantastic job, but Craig over at A/C svc may have you beat. Lol. Seriously though, I just subscribed and I'm looking forward to watching more of your content.

[@billbroadway5972]

Your timing couldn't be better.I'm a homeowner installing a 3 head unit. Got an est. of 15K. Thanks to your videos you saved me about 5K inc. tool purchases!

[@stuzman52]

Bill Broadway Glad to help out Bill!

[@WillianPortela]

Perfect Work! Greatings from Brazil

[@stuzman52]

Willian Portela Thank you very much!

[@mosfet500]

Thanks Stuzman, I really enjoy your presentation - big help!

[@stuzman52]

Glad to hear that you found the video helpful! Have a great day!

[@noz455sd]

Nice! Exactly how I installed mine.... tools too but I snagged a cheap US made vacuum pump 😉. You did your homework and to anyone watching this is how it’s done

[@stuzman52]

Thank you Chris and not many people willing to take the extra steps as you did to do it right!

[@doddgarger6806]

Yeah I got a robinair on eBay for $75 guy only used it a couple times tired of renting them!

[@mathieulamaure1487]

Excellent step by step video! Thanks a lot sir!

[@stuzman52]

You are quite welcome Mathieu and thanks for leaving a comment!

[@AliBaba-cf4iu]

Mr....... you are very neat and you do an excellent job extremely neat thank you ,keep them coming

[@stuzman52]

Thank you very much Ali!

[@barryfitzgerald5803]

I have never installed an AC unit and been reading up on them. I am not an installer and have considered doing my own as the cost locally are really high >$30k for 2k home. I am an engineer so technical but there are so many things one does not know that they don't even know they don't know. The video was very detailed and you really like to be precise and that was great to see. I may just take the task on for at least my home office. I hope I have the patience to do it right like you did. I wish you were nearby and I would be your customer.

[@stuzman52]

Thank you Barry for the comments! As you are an engineer, you know that any project is all about the details. I'm quite sure that if you were to install your own unit, you would research those details that you weren't sure about, and you would have an installation that you would be happy with. Thanks again Barry and have a great weekend coming up!

[@TheOriginal_T-Bilt]

Dude... that was an excellent how to... Very well done! THANK YOU!

[@stuzman52]

Thank you very much TG and have a great day!

[@frankg2167]

best explanation , tools and procedure . i will follow your videos , thank you

[@stuzman52]

Thank you Frank and best wishes on your install!

[@garyleonard7441]

This guy has done this before A professional nice job

[@stuzman52]

One or twice before Gary... :)

[@CentralPerspective-my2ev]

Looks like a beautiful installation..

[@stuzman52]

Thank you for the comment! Unit still works great today. Have a great day!

[@ericsolberg8812]

Clean work. Great job

[@stuzman52]

Thank you Eric!

[@BhumitPatel]

you are awesome!!. you have explained it so well!

[@stuzman52]

Thank you very much!

[@crowderglen]

Great video ! This is the only way to perform the vacuum procedure. After valving off the core removal tool, I’ve never before seen the micron gauge continue to decrease. I’ve always had it increase slightly as the vacuum equalises throughout the lineset

[@stuzman52]

Thanks Glen for the comment and have a great day!

[@fatnate1000]

I am planning on installing a mini split for my 2nd story and wanted to know about making line sets. I stumbled across your video, and in the beginning thought you were too detailed. But after watching the entire series, i understand why. You Sir, are a dedicated individual. KZbin could use more individuals like you that are more geared towards making sure your viewers understand the process and not trying to make Discovery Channel entertainment.

[@stuzman52]

Thank you fatnate1000 and I always believe that if one wants to do a job, I'll try to make it detailed so that an individual can see the steps involved. Yes, if I was to make a three minute, what would be the point of making the video if you don't know how to do the job. Thanks again for watching the series as I appreciate it!

[@bobbyz7736]

Ok, I feel like an idiot. But it's my first mini split install. I pressure tested and evacuated my first lineset, then released the refrigerant into that lineset. I thought, Oh boy let's try it out. Head unit blows hot air, condenser fan is running , but no cooling going on. Ok, I figure I must need to hook up the other linesets to lower refrigerant pressure. I'm rewatching Stuzman doing his release of refrigerant and then I see him open another valve on the pressure side of compressor. I think, wow, I didn't open the valve on high side. I open it, then turn system on and to my amazement, the head unit starts blowing cool air!! What a Newb I am!! I'm glad I rewatched his video. He saved my day. Now to hook up the other two head units to the compressor. I'm really jazzed!!! Thank you Mr Stuzman!

[@stuzman52]

Good for you Bobby and don't knock yourself! Hell, me and countless others have done things that we would never admit 😊 Have a great evening!

[@russellmartin2705]

Great technique, sanitary install, knows how to use wrenches, like the attention to details like nylog on caps.

[@stuzman52]

Thank you Russell for the comment and be sure to have a great day!

[@donnfl]

Great video. Very nice Job.

[@stuzman52]

Thank you very much!

[@subron14]

Great job very detailed!!!

[@stuzman52]

Thank you very much Gary for liking the video and sharing a comment!

[@normansmith7806]

Good series !!

[@stuzman52]

N Smith Thank you Norman!

[@trenth6594]

Very well done!

[@stuzman52]

Thank you Trent!

[@hkcitation]

Well I have been thinking of installing a mini split and your video has shown me that with afew more tools it can be done.

[@stuzman52]

It's not a bad job at all. As you said, just a few tools, take your time and you should have a great installation.

[@icemachines69]

My favorite video, I thank you...

[@stuzman52]

You're welcome...

[@neallyons9515]

great job! i have to laugh at other "installers" that don't even own a micron gauge, and they're trying to teach others. Thanks so much

[@stuzman52]

Thanks Neal for leaving a comment!

[@Froggability]

Or they don't even own a vacuum pump, heaps of countries just "purge" no vac

[@chicchoc9]

@@Froggability I think this video and use of correct equipment are top notch. That said, as a DIY guy, and not thinking I would install more than 1 or 2 units, for myself, i chose not to buy a fancy vacuum pump. Instead I unscrewed the intake valve on my air compressor and screwed in a couple of fittings to connect to a cheap set of gauges. I do purge with nitrogen and bubble test and then vacuum down to almost neg 30 " HG with my old compressor.. I don't let all of the nitrogen out before vacuuming- i vacuum it out so no air and moisture can enter. Having now installed 7 in the last few years, and with 2 more to put in soon (all for family for free) I could now have justified the real vacuum pump and micron gauge, but I have gotten by fine with only the manifold gauges. A micron gauge would be sweet to have, but if you clearly have no leaks in the bubble / pressure test and then you vacuum it all out, you will be fine with only rudimentary gauges. The expensive tools are great if you want to do a bunch, but not essential. Great video Mr. Stuzman. Many DIYers will benefit and step up to do this now.. I even had two units need recharging (one developed a pinhole leak in the factory brazing around the reversing valve after 3 years and one had a faulty expansion valve). I was able to buy a bottle of R410 at a decent price on-line and ship from USA to Canada no issue. Brazed in new parts each time, pressure/bumble test, vacuum and weighed out refrigerant charge on a good (borrowed) set of scales as i charged unit... that was several years ago and still going strong. Its not rocket science- watch good videos like this one, but basic tools and save some cash!

[@mosfet500]

Thanks again Stutzman. Here's what I did to vacuum my last mini install. I nitrogen tested my system, - tested good. I then slowly released the nitrogen until my gauge read low. I immediately put the valve removal tool on the mini port and the micron gauge directly on the valve removal tool.(mini core was already out). I vacuumed the system down to ~110 microns and shut the core tool valve off and let it sit for ten minutes - still held 110 microns. I then put the valve in and let a little refrigerant into the lines to build pressure, when everything was good I let all the refrigerant in tested for valve leaks and then removed the valve removal tool. My thinking is that the fewer connections the better, my system vacuumed to ~110 microns.

[@stuzman52]

Sounds like you did a great job! Yes, you want the fewest connections when you're pressure testing or pulling a vacuum. Keep up the good work and have a great day!

[@mosfet500]

@@stuzman52 Thanks. I think one thing I would change is that instead of replacing the valve at max vacuum I'd bring up the pressure slightly so that the it's just slightly positive 410A side so it's pretty much in balance. I did check the Appion valve tool and with vacuum it's showing ~18 microns with the valve opened. By the way the CPS Vg-200 meter is good for 450 psi with a burst of 3k psi, so even if it was full pressure from the mini it still wouldn't have a problem although I don't like to test that. As always you've been great help and I very much appreciate your videos and input.

[@stuzman52]

@@mosfet500 Thanks for your comment and sharing your experiences with your mini-split. Have a great day!

[@richardmckrell4899]

Nice video, I''ve never put nylog on the port caps but may try it

[@stuzman52]

Thanks Richard and never hurts using the Nylog on any threads. Have a great Thanksgiving!

[@fengtaowang5348]

Great video. It would be a good idea to exercise the valves of these 2 Core Removal Tools during the vacuum process. There are some air sealed inside these valves.

[@stuzman52]

Yes, that is a good point Fentago. Thanks for the comment!

[@Rmilms]

Great video, I really like how Americans do things, Here in Australia we do everything half assed.

[@stuzman52]

Thank you Ryan and trust me, we have our share of half-asses over here too 😊Have a great day!

[@Rmilms]

@@stuzman52 haha, yeah I bet.

[@user-lm8zk6qz2m]

love the work of fakum and I like

[@stuzman52]

Thank you very much!

[@tompace6916]

I'm certain I'm not the only 60 year old that has a difficult time reading blue letters😂. The video is excellent as always 👍👍👍

[@stuzman52]

Thanks Tom!

[@neallyons9515]

one of the few diy vids that actually does it right. Gotta love the guys using dial gauges in other vids and saying they work good enough, yeah they work good enough to get the job done and get out of there before the compressor blows. Really tho anyone not using a micron meter might get lucky but it's just that, luck, cause you really don't know..

[@stuzman52]

You are correct Neal! Without a micron gauge, you never know how much vacuum is pulled on a system.

[@jdarrellsteele3264]

I think this video and use of correct equipment are top notch. That said, as a DIY guy, and not thinking I would install more than 1 or 2 units, for myself, i chose not to buy a fancy vacuum pump or micron gauge. Instead I unscrewed the intake valve on my air compressor and screwed in a couple of fittings to connect to a cheap set of gauges. I do purge with nitrogen and bubble test and then vacuum down to almost neg 30 " HG with my old compressor and regular gauges.. I don't let all of the nitrogen out before vacuuming- i vacuum it out so no air and moisture can enter. Having now installed 7 in the last few years, and with 2 more to put in soon (all for family for free) I could now have justified the real vacuum pump and micron gauge, but I have gotten by fine with only the manifold gauges. A micron gauge would be sweet to have, but if you clearly have no leaks in the bubble / pressure test and then you vacuum it all out, you will be fine with only rudimentary gauges. The expensive tools are great if you want to do a bunch, but not essential. Great video Mr. Stuzman. Many DIYers will benefit and step up to do this now.. I even had two units need recharging (one developed a pinhole leak in the factory brazing around the reversing valve after 3 years and one had a faulty expansion valve). I was able to buy a bottle of R410 at a decent price on-line and ship from USA to Canada no issue. Brazed in new parts each time, pressure/bumble test, vacuum and weighed out refrigerant charge on a good (borrowed) set of scales as i charged unit... that was several years ago and still going strong. Its not rocket science- watch good videos like this one, but basic tools and save some cash!

[@neallyons9515]

@@jdarrellsteele3264 I wouldn't let you install a heat pump in a dog house. Yes your setup may let you know if there's major leaks, BUT that's all. Most heat pump manufacturers call for 500 microns or less, (which you can't even read with a dial guage) and there's a reason for that. There could be moisture in the system for example and you would never know it without the micron guage. When your cousin tony's compressor dies after 2 years you'll be like, man we won't be getting that brand again! When in reality it's actually your fault because you were just rolling dice hoping for the best. I installed ny first pump with dial guages 4 or 5 years ago and it's still going strong, but I realized later that I got lucky, simple as that..

[@jdarrellsteele3264]

@@neallyons9515 I do appreciate you saying that you have previously installed them with dial gauges and have since learned better. Learning is the reason I re-searched youtube, after not having installed any in about 3 years now. The 7 that I have installed have all been running between 3 and 7 years, but as I have 2 more to do soon, I wanted to see if any better videos existed than what was out there several years ago. I am glad I did. I am considering buying the CPS digital/micron gauge but will likely not put in many more after these two. As mentioned, I have only done this for family members for free.. they know our setup is crude and I will talk to them about the option of chipping in a bit to cover the costs of the gauges if they want to ensure success or if they prefer to do as we have before. I agree that I do not know how complete of a vacuum I have achieved, when using the dial gauges. But, the compressor is strong enough to pull the dial gauges down quickly and then I leave it running for a good length of time after that, knowing that it is continuing to pull finer amounts out the longer it is left on. re: possible moisture left in there, I doubt that would be the case, as I have purged the lines (and indoor coil) with nitrogen (cracking the opposite line fitting and letting all of the air out followed by a couple of minutes of nitrogen before tightening the fitting and pressure testing.) Then this is all vacuumed out, without letting air back in.... I release enough of the nitrogen to be at a few psi and then I turn the compressor on, and slowly open the valve. So, i could have some small amounts of nitrogen in there (knowing this is not ideal either..) but there is no chance of moisture being in there. If I do decide to buy a micron gauge, It looks like it's best to then buy 2 core removal tools and the reviews on cheaper ones are not great... the ones linked in this video have great reviews but at about $53 USD or $90 Cdn for me, two of these plus the CPS micron gauge( least expensive one i have seen with good reviews) adds another $220 Cdn so all totalled it would be pushing $500 Cdn for this added ability. If i have 5 more to do, it would be an easier choice. Still I would then be increasing chances of success and would have them for the future, if any of the others need work/ recharging, etc.

[@miketalaski1616]

The only thing I may add is I would put the service valve cap on loose to check for leaks out of Schraeder port. Seems easier to check for leaks when I can maybe just see a few bubbles.

[@acechoice45]

Nice Vacuum Rig A+++

[@stuzman52]

Ace Thank you Ace!

[@matthewking6509]

Loving what your doing I actually run the same setup . However knock the second t off BluVac is pressure rated and refrigerant doesn’t effect the gauge at all just clean out with alcohol if any issues . The extra removal tool is just extra connections for leaks .

[@stuzman52]

Yes, Matthew, you can use the setup as you're referring to.

[@billyr9840]

Nice !

[@KokoMagicToys]

VERY NICE !! liked :) :) thank you :) :)

[@stuzman52]

Koko Magic Toys You’re quite welcome!

[@josederibamarrodriguesdoss3082]

bom dia parabéns pela pasciencia explicando passo a passo com todo detalhes sou seu fã

[@stuzman52]

Muito obrigado pelas amáveis palavras. Fico feliz em saber que o vídeo ajudou. Tenha um ótimo dia!

[@richiebusciglio8272]

The best mini split video on KZbin!! Where are you located? Are you available for hire? Thanks Rich

[@stuzman52]

Thank you very much Richie! I just work on my own stuff and now retired.

[@Zack7228]

Hi Stuzman....I hope all is well. It's been 3 years since you helped direct me on some questions that I had on installing a mini split at my previous home. I have since moved to Colorado...and am installing 4 more Bosch mini splits. I made a stupid mistake the other day when trying to commission the first one... I vacuumed it down to 150 microns...and it held 170 for about an hour. I normally always break the vacuum with nitrogen, check for pressure leaks, and vacuum down again. Well...I ran out of Nitrogen so...I just followed the normal procedure. Unfortunately...I didn't check all the connections immediately after releasing the refrigerant. The line set connection to the indoor unit on the low pressure side blew out refrigerant. I didn't realize it until I started troubleshooting the next day when it stopped blowing warm air. The indoor unit is supposed to display a code for low refrigerant...but it did not. I put my pressure gauge on the service valve...and it was minimal if at all while running the AC. My plan was to recapture what refrigerant was remaining in the compressor...but since there was no pressure to speak of...all I could think to do was to close the ports to hopefully protect the compressor from air in system? I am getting my nitrogen refilled to hopefully not repeat same mistake. I don't mind buying refrigerant and scale and trying to correct my mistake. Curious as to your thoughts if I should have a service call to retest and refill...or make the investment? Thank you...

[@stuzman52]

Hi Steve! Since you probably won't make this mistake again, you probably wouldn't use the scales again and it may be an issue to buy R410a if that's what your system is using if you don't have a certification license. Maybe the service call would be the best. Have a great day Steve!

[@timturner4475]

Love these videos of yours! Quick question about the mounting system that you have attached the condenser to; could you provide a source url etc., for the frame & is that a regular paving stone you have it anchored to?

[@stuzman52]

Glad to hear Tim that you're enjoying the videos. As for the outdoor unit stand, it was ordered from Amazon where the link is here. www.amazon.com/gp/product/B0192298O0/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1 I shortened the legs a little, replaced all the fasteners with stainless steel and repainted the assembly. As for the pad, I poured a concrete slab for it. Have a great day Tim!

[@kevinkevin9448]

Watched it over and over great video greeting from NJ

[@stuzman52]

Thank you Kevin and greetings back at you from NC.

[@natahalub]

Блестяще! Респект.

[@stuzman52]

Thank you very much!

[@daveyboy8907]

Is that the pioneer stand? I am about to order my unit and tools..Thanks for the videos you do it right with no missed steps...Its worth it to me to spend the extra money on the tools and learn.. Its still way cheaper than hiring a guy who may or may not do it right.

[@stuzman52]

Hi Dave! The stand was ordered from Amazon and is located here www.amazon.com/gp/product/B0192298O0/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1 I made some modifications to the stand where one was to shorten the legs. Yes, it helps to have the correct tools to do the job and you are correct that it's not a guarantee that a professional will do the job correctly. For the same size unit as mine, my neighbor says that a contractor wants $5000 to install it. That's a pretty hefty price. Have a great day and good luck on your install.

[@Kntryhart]

One more question if you please... I purchased a Senville 18K BTU Heat Pump H.S. pressure is 550 psig; L.S. pressure is 340 psig. When you performed a leak test, the lines were pressurized to 200 psig. Was that for a reason? I see others going up to 300 psig. Thanks! JT

[@stuzman52]

No particular reason on the 200psig. Even at this pressure, you'll still be able to see a leak. In your case, I wouldn't push the pressure near the maximum of your lowest test pressure that was used at the factory. In your case, I would go for about 250psig and you'll be fine. At 300psig, you'll be getting pretty close to 340psig. At 250psig, you'll be allowing yourself a little margin of safety. Good luck on your installation!

[@antniocris9744]

Great Viseo Thanks, I Have the Same Unit it lasted 1.5 Years the Comp Went recovered charge, No Loss, Seems either I got a bad One or they are making bad units! Bye Mitsubishi They Last Put many in for Cust. w/ No problems!

[@stuzman52]

Maybe just a bad unit, but who knows for sure. Hopefully, the Mitsubishi units will last longer.

[@SteveRobReviews]

Nice and cool now, Terry you're the only now with ac in their shop so is that cool or what LOL

[@stuzman52]

STEVE ROB REVIEWS It’s pretty cool now and I seriously doubt that I’m the only one with ac in their shap. 😜

[@lasezonedify]

Hi have 24000 btu air split runing in heat mode whet temp 70 it runing worm but put the unit to the more 80 and temp no change can u help me why no heat more thank you

[@45von]

Nice set of videos... I am assuming that for a typical instillation of a mini split the condenser is precharged with enough refrigerant, is there a run length that would require larger tubing OR an increase in refrigerant charge? also, when checking that system at any future date, there appears to be no high side port, how is that done?

[@stuzman52]

That is correct that this unit along with other manufacturers comes precharged with the correct amount of refrigerant stored in the condenser. The unit is charged for a maximum line-set length of 25'. You can go as short as 10' in the line-set length without any issues. If you go shorter or longer than indicated, then you'll have to evacuate the refrigerant and adjust the amount according to the installation manual. For example, 0.16 oz/ft if the length exceeds 25'. As for the size of the tubing, that is shipped with the unit and it's size is based on the BTU rating of the unit. And as for their being no high side, if there is a suspicion that the low side is reading too low indicating maybe a low charge, then the system must be evacuated and recharged by weight, same as on an automobile.

[@Kntryhart]

Would you recommend, or see a problem with applying, a small amount of NYLOG BLUE to the Schrader Valve? Thanks!

[@stuzman52]

No problem at all at applying a very small amount of Nylog blue to the seal on the schrader valve. Also, you could apply a small amount of Nylog to the cone of the flaring tool as a lubricant when making your flares. And you could apply a small amount around the flare fitting. And be sure to torque the flares and not use an adjustable wrench to be sure that they're not over tightened.

[@Kntryhart]

@@stuzman52 Did a pressure test this morning (250 psi for 3 hours; rock solid! Pulled vacuum down to 64 microns in about 25 minutes (new pump and oil). Will see what the vacuum level is tomorrow. Maybe even do a test run! Thanks for the videos!

[@stuzman52]

All sounds good! Good luck on your installation!

[@Kntryhart]

@@stuzman52 Up and running! I have a brand new Appion MegaFlow suction hose (p/n MH380006EAB) 5/16" one end / 1/4" other end. I will never use it since the pump I got has just 1/4" fittings. If you could use it, it's yours - no charge. Look at as a token of my appreciation for the excellent mini-split videos you posted! Let me know...

[@douglasthompson2740]

I am interested to know how you routed the compressor's condensate drain to prevent a large winter ice block forming under the (and maybe in!) compressor in the winter? Good video. Doug

[@stuzman52]

The condensate line under the compressor was cut off at the top of the mounting bracket. It's about 12" off from the concrete pad.

[@garysmith9772]

Terry hope all is well we miss your vids

[@stuzman52]

Sorry for the delay Gary as KZbin did not notify me. All is well and coming up with some ideas for new videos :)

[@genepierson]

Thanks for sharing. Best video out there on evacuating a mini split. QUESTION: Is the core removal on the CORE REMOVAL TOOL, overkill? How much refrigerate would be lost otherwise? (I'm not against overkill. I just wonder if pros do it, or just overkill?)

[@stuzman52]

It's a standard practice in the field which allows the vacuum pump to pull a deep vacuum without the restriction of the valve core and it does speed up the evacuation process. I have seen others in the field not do this in order to save time, but in my opinion, it's a better method when doing a evacuation.

[@stevebates6281]

Enjoyed the video. If the unit was empty would weigh the refrigerant in using the liquid line port off the compressor or would you add it on the suction line port where the line set attaches. Trying not to flood the compressor. Thank you

[@stuzman52]

You'll only have one port to add the refrigerant. I would just put the refrigerant in as a liquid without the unit running. It's the same procedure when charging a vehicle. It's charged with a liquid without the engine running. As the liquid goes into the system, it will flash into a gaseous state. And since the unit is not running, you don't have to worry about flooding the compressor.

[@ldlink3935]

I'm curious, what steps would you have taken if you had seen bubbles coming from the valve core after you reinstalled the valve core? at 9:49

[@stuzman52]

In a case like that, I would remove the valve core and installed it one more time and recheck for bubbles. If there were still bubbles, then I would replace the valve core with another one. :)

[@larsern2752]

One quick question. When you put the valve core back into the service port, Wouldent there be a small air pocket in the valve core removal tool that gets into the system??

[@davidwise9119]

To install the valve core under vacuum with minimum contamination, I'd say put the gauge on side port 2 and the vacuum hose on extremity 2 instead of 1, and keep pulling while you open 1 and install the core. Better to install it without vacuum. Crack the gas service valve until the gauge reads ATM, close the valve, remove the gauge and install the core.

[@dmac2890]

I like your Videos, how is that unit working?

[@stuzman52]

Still working good!

[@coolmingli]

Thanks for the video, one question, can I put the valve core back in before release the refrigerant?

[@stuzman52]

Not the best idea as you will allow the atmospheric pressure back into the system. Always best to install the valve core while system is pressurized.

[@rod8420]

excellent video. step by step. i have a question. can i use 1 stage pump to vacuum a mini split or do i need the 2 stage? thank you.

[@stuzman52]

You can use a one stage vacuum pump. It will just take a longer time to reach a deeper vacuum. But a micron gauge will let you know when you reach at least 500 microns.

[@gabaknegocios]

in order to install a mini split is it a must to use a vacuum? or with the nitrogen alone is enough?

[@stuzman52]

In order to find small leaks, you should pressurize the system with nitrogen. If you use vacuum, you may not find a small leak. And if there is a leak, how are you going to know where the leak is under a vacuum? Also, it is a MUST that you vacuum the system of air. Have a great day!

[@jaylandry8915]

Are you able to do this without a valve core removal tool or is it recommended? Thank you.

[@stuzman52]

Jay Landry It’s a recommended procedure done in the industry, but it can be done without a valve core removal tool.

[@AndreyKan1]

Great video, I am watching it again and again, and the more I understand the procedure the more questions I get :) 1. In the video about nitrogen test you used yellow jacket. Am I right we can just use the same micron gauge for the nitrogen pressure test? 2. I watched another video about triple evacuation - so one difference I found important: they first create a vacuum, and then introduce nitrogen, while you just introduce nitrogen into unpressurized lines. I would guess vacuum-then-nitrogen is cleaner. Any comments, please? Thanks again

[@stuzman52]

In regards to your question #1, no, the micron gauge should not be used to measure the pressure of nitrogen in the system as the micron gauge is designed to measure vacuum. And you'll find that it can't measure pressure above atmospheric pressure. On mine it won't register any pressure until it gets to below 20,000 microns which is about 0.38psig. As for triple evacuation where one begins the evacuation with nitrogen is not really needed as it takes hours to assume that the nitrogen will absorb the moisture. Or that it really doesn't absorb the moisture but displaces it. The vacuum pump will lower the pressure, boil the water vapor at a lower temperature and then the pump will evacuate the water vapor. Here is an article where this is discussed it and in my opinion, triple evacuation is not really needed. hvacrschool.com/triple-evacuation-and-nitrogen-facts/

[@west6919]

The Daikin unit I am putting in my shop per the manual says a minimum of 10 ft of line set. I am going to be pushing that-it may only be 9 ft as inside unit is close to condenser. What is the reason for the minimum? Is it because of the factory precharge? Thanks and enjoyed your videos.

[@stuzman52]

Yes Ted, you are correct! The manufacturer wants a minimum length based on the precharge that's in the outdoor unit. The same holds true for a maximum length of line-set too. Glad to hear that you liked the videos.

[@jarrettsmith9003]

Hi, thank you very, VERY much for sharing your knowledge. I'm also a DIY fanatic like Norman below, and I would like to get some HVAC tools and equipment to install 5 mini-split units that run with 410A. What suggestions do you have for a vacuum pump (say a two stage, 6 cfm), vacuum gauge, and manifold? A list of tools would be great. THANK YOU in advance.

[@stuzman52]

Thank you Jarrett! Yellow Jacket or Hilmor offer professional tools in all categories of refrigeration. You can go to their websites to see what they offer and good luck with your installations.

[@6thDAY]

I have a pre-charged line set that has been vacuumed and filled with R-410a refrigerant from the factory, but I need to shorten its length. Since the lines are factory pre-charged, is there anything special I need to do aside from vacuuming the lines and checking the microns before releasing the R-410a refrigerant from the condenser?

[@stuzman52]

If you can recover the refrigerant from the lines, everything will be as you mentioned except maybe doing a pressure test of the line set before evacuating.

[@w1swh1]

Thanks great video, Also watched nitrogen test video. Excellent. Just one question. Are the procedures the same for a multizone mini split? I have 4 zones on the outside unit but only using 2 zones. Best regards.

[@stuzman52]

Yes, Derick. You would do the same procedure for each zone that you're using.

[@w1swh1]

Thank you, appreciate it. Here goes🙂

[@luisquiroz2412]

Did you remove the core depressor off the micron coupler or doesn’t matter if it’s there?

[@stuzman52]

Hi Luis! The micron gauge coupler that I used doesn't have a depressor for the schrader valve. However, I did remove the schrader valve from the core tool that the micron gauge connected to. It really doesn't matter whether this schrader valve is removed or not. Have a great day!

[@douglasknutsen]

Sir, can you please give me the Brand names and part numbers of the valve core tools and the connectors that you used to attach to the service valve and also did you remove the schrader valves from the yellow line when you were pulling down the vacuum in the third video . Extremely well done videos , thanks.

[@stuzman52]

Sorry Douglas Knutsen as KZbin did not contact me. It's getting a little late Douglas, but if you send me a private message with your email address, I'll look up the parts and answer your questions tomorrow. And thank you very much!

[@hectorgalan408]

very good video i use 30/30 30 minutes vacume 30 minutes wait for leaks if is ok charge the refrigerant

[@stuzman52]

That will work also but not a guarantee that the system is sealed tight. Higher pressures such as when using nitrogen will tend to show very small leaks where it could take hours or days when checking for leaks using vacuum only. On one occasion with an automotive a/c system, I left the vacuum overnight and the vacuum readings looked good the next day! Then the refrigerant was added into the system and several days later, a very small leak was found. Now to be sure of small leaks, I'll add nitrogen to the system to look for very small leaks.

[@hectorgalan408]

@@stuzman52 you are 100% correct

[@Thomas-wn7cl]

Any problems with the Pioneer split unit since installation Mr. Stuzman? I have been looking around for who makes the most reliable units.

[@stuzman52]

None at all! It's been working great since I installed it last year.

[@Thomas-wn7cl]

@@stuzman52 thanks

[@hodesto]

Did you choose the Pioneer because you like the reliability and reviews?

[@dontworrybehappy9713]

Tools used in video links?? Also what gauges do u recommend?

[@stuzman52]

I have included a link to the manifold gauges and low loss hoses used in the video. The other tools used are already located in the description of this video.

[@JSROOKS]

Great. I never saw you check the pressure on the high or low side after refilling the system however. I would think that you would do that when you first turned the system on for at least a few minutes. If you had lost some refridgerant, your low-side pressure would be too low, wouldn't it?

[@stuzman52]

It's not necessary as the amount of refrigerant in taking off a line is minimal which is not going to effect the low side pressure to the point where the unit will not work.

[@kawscottyoung]

What is that valve/adaptor assembly called with the port for the micron guage and special shraedor valve R&R tool?

[@stuzman52]

That would be a valve core removal tool. The port on mini-splits are 5/16" so a valve core removal tool for that one would be used. Here is a listing for it www.amazon.com/Appion-MGAVCR-Vacuum-Rated-Removal/dp/B008HQ2EZ8/ref=sr_1_19?keywords=appleton+valve+core+removal+tool&qid=1638742856&sr=8-19

[@kawscottyoung]

@@stuzman52 !! Thank-you !!

[@abhinavgaur13]

Hello Stuzman for the video explanation. Could you please tell me why we do not conduct Nitrogen pressure testing on a mini-split system as we do in case of regular HVAC systems at the time of installation? I recently purchased a Mitsubishi MUZ-GE24NA and its installation manual requires to perform only the vacuum procedure and nothing is mentioned on the pressure test. Thanks

[@stuzman52]

Yes, Abhinav, the manuals for mini-split units are written towards people, (DIYers) who do an installation themselves. The manufacturer realizes that most DIYers will not have a supply of nitrogen, pressure regulator, etc. for the test. So, they will mention to pull a vacuum on the system and if you see the pressure rise, then you have a leak. The issue is that under a vacuum, you can have a very small leak and will never know it. Once I had a system under a vacuum for 24 hours and never saw the gauge pressure rise. After about one month when the cooling was insufficient, I found a leak. So, to be sure there isn't a leak, the valid test is to pressurize the system with a high pressure of nitrogen. Also, the reason that you see nitrogen pressure testing on standard HVAC units is because most of these units are installed by professional a/c service techs who will have that test equipment. Great question and thanks for the comment!

[@abhinavgaur13]

@@stuzman52 Thank you for your prompt response. Listening to you and another great channel called "AC Service Tech LLC", I finally understood why Testing for leaks under high pressure and under high vacuum are testing different design aspects of the system. Furthermore, your video where you have explained the difference between a Vacuum Gauge and a Micron Meter was amazing which clarified a lot of things, that's why the question. :)

[@stuzman52]

Abhinav Gaur Glad to help Abhinav and AC service tech is a great channel where you have access to a wealth of information!

[@fantom_1]

Hi, do you remove the core from the Micron Gauge as well?

[@stuzman52]

I didn't remove the schrader valve for the micron gauge. Have a great day!