Step by Step How to Vacuum Down Mini Split Using Analog Gauges Release Refrigerant Check for Leaks

[@sevoserver912]

I just installed a Tosot 230V 9000 BTU mini split in my pool house. I found this video extremely helpful. This was my first install but I’m pretty handy with electrical and building. For vacuuming the lines and releasing the refrigerant I found your video the most helpful and clear. Thanks for posting your video!

[@RonSellsArizona]

Thanks so much. I'm seventy two and have always been my own Mr. Fixit. But this was a first for me. I have watched several videos on the subject and this is the best. Articulate, concise, and Very Very helpful. Thanks so very much. Oh yeah, totally worked fine and I am now cool.

[@charlesgreen9468]

Cool 😎😊

[@kstewart8014]

This is the best video hands down that I have seen on YT in regards to this,especially learning how to keep the refrigerant If you do find a leak. Your the Hero we all need but don't deserve. Thanks man.

[@erinmagers2970]

THANK YOU!! Your videos gave me the confidence to try this and save $1000 (quote from multiple HVAC people).

[@daviddiaz7767]

I do everything around my home but have always been afraid of the HVAC system. Thanks for explaining things so well and making this feel easy. New tools and skills in my toolbox. Thank you!!

[@UltratecJS]

Great video my friend. I went from guessing on what I was doing with my DIY mini split install, to actually understanding what's happening on the back end.

[@davidmclain1875]

Man...great video. I've watched a dozen of these vids on minisplits. Thank you for making one just for the vacuum portion of the install.

[@billbill1605]

Excellent tutorial no nonsense right to the point all this needed thank you so much

[@RiBar84]

Perfect! Thanks for the help!

[@dannyf4995]

Thank you for the clear and helpful video.

[@pointblank6467]

Excellent video! Thanks for all the details.

[@mathieulessardr]

thank you I will install my heat pump this weekend👍

[@retiredandroaming]

Do you smear anything on the flares/line fittings when installing them on both units or is everything always installed dry? I've heard of blue nylock?

[@jamesorlando7134]

Can u recommend the brand equipment to use for this procedure?

[@HVAC_Mechanic]

I'm just using a low-cost HVAC gauge and pump. The links are in the description for what I am using but any low-cost HVAC pump and gauges will work.

[@joshtapia9636]

why does my blue hose (low pressure) fit directly on to the service port? do i need that adapter still? Im starting to think my service port is 1/4?

[@kellywhite3633]

I was told by a hvac expert to release the small line valve first slowly, any reason for this?

[@HVAC_Mechanic]

A lot of techs will argue about that one. Many manufacturers' manuals state to open the suction line first while others don't. It's always best to follow the manual from the manufacturer. Personally, I don't think it matters.

[@noealanis1801]

Is the adapter the same for all mini splits?

[@danle2884]

Hi, when you connect the lines to the outside unit, do you need to use Nylog and a torque wrench like the manual says? Thank you so much for the video.

[@HVAC_Mechanic]

It depends on the installer. I use Nylog but have never used a torque wrench. Some installers never use either, while some use both. The main thing is to get the fittings tight enough not to leak without overtightening them.

[@macleanclassics]

Question: why do some videos show a shrader valve step ? Is that not required ?

[@HVAC_Mechanic]

Removing the Schrader valve is not necessary; sometimes, it is done on very large HVAC units to pump them down quicker, but even then, it is not necessary. A lot of people get their information from schools and books, which very often is not how it works in the field.

[@stanwalls6434]

That was great thank you it well until I unscrewed the blue hose from the adapter instead of the unit and lost a lot of coolant before I got the adapter off #####**, so he much damage did I do? The unit is working and blowing cool air, thanks.

[@HVAC_Mechanic]

If the unit is working, you didn't lose enough to affect it.

[@stanwalls6434]

@@HVAC_Mechanic thank you it was about 2 secs but really released. The out side lines are really wet, if it freezes then I’ll need to recharge?

[@HVAC_Mechanic]

There can be different symptoms, but if the unit stops blowing cold air, then it likely will need a recharge. Hopefully, the unit keeps working. When low on refrigerant officially, the refrigerant in the unit is recovered, and new refrigerant is added in by weight. Unofficially, refrigerant can be added in very slowly in increments until the unit starts blowing cold air. R410a can be bought online such as Ability Refrigerants. Anyone can buy refrigerants, but technically, you're supposed to have an EPA 608 card to use it. I made a video on this, here is a link. kzbin.info/www/bejne/gqOwgoKEd699nac

[@stanwalls6434]

@@HVAC_MechanicI really appreciate you taking the time to respond thank you sir. Room is cool but concerned about the lines and fittings being dripping wet down to the machine. Should I worry about that? Thanks

[@tamdang2566]

Thank you you have show how to vacuum this system so all mini split requires vacuum right?

[@HVAC_Mechanic]

If there is outside air in the lines, then yes, a mini split needs a vacuum. There is quick connect type mini split units that don't need a vacuum and come with the line set already in a vacuum.

[@sh0ckwaveVR6]

I got a mini split installed and the technician leave the vacuum pump running for only 10 minutes. should I be concerned?

[@HVAC_Mechanic]

It is likely good as long as it holds a vacuum.

[@CaptainCorpuscle1]

To which port do I connect the blue hose? I’m assuming it it the one marked “low pressure charge plug” but I want to be sure. I seem to have two ports, and the one i think it is does not need an adapter

[@HVAC_Mechanic]

If there are two ports, the blue hose goes to the low-pressure big line, and the red hose goes to the high-pressure small line.

[@amirzulkafli]

Hi, will a 2 cfm single stage vacuum pump do the work for a 1.5hp split aircond system?

[@HVAC_Mechanic]

Yes, it will work. Most any HVAC pump will work; it's just how fast it can pump a system down.

[@adrianeligio6540]

Hello Sir, I have installed a senville mini split have installed everything but one issue it does not hold the vacuum. When start test it the gauge stops at -15 and not at -30. My area is at 5500 feet can that make it set on -15 instead of -30. It does not hold pressure. If I disconnect the hoses and re connect cause and retest the vacuum even do I have not release the coolant from fan. If you can help with this question will be appreciated.

[@HVAC_Mechanic]

As long as the vacuum pump is good the elevation shouldn't matter it should pump it down into a vacuum. It may be best to test it for leaks with nitrogen, you can also get a can of KWIK-E-VAC Line Set Flushing Kit pressurize the line set and then check for leaks with soap. Here is a link to KWIK-E-VAC on Amazon. amzn.to/4dkqkhI

[@windsbra12]

Are you using a manifold gadge ? Is so make sure there are no srader valves without caps. Vacuum will pull air around the srader valve . Some pumps have more than one port and don't come with a cap fpr thw second port. All srader valves need a cap

[@HondaVTECGD8]

If both valves are shut closed, how does the vacuum pump able to do its job vacuuming those copper pipes?

[@HVAC_Mechanic]

The unit is shipped in a vacuum with the refrigerant and locked in with the valves. Once the copper line set is in a vacuum, the refrigerant can be released by opening the valves.

[@garytodd5605]

A micron guage along with vacume guage will show you a lot . Your vacume guage will give you confirmation that your system has a vacume on it if it is depressing the shrader valve correctly. The micron guage will give you a much better indication of moisture in system. My guage went to almost 30 inhg very quickly. but the micron guage was taking forever to drop down. To below 500 i would like to see 300 or less on the micron guage. Then prefer it stays under 500 after about ten to 15 min isolation test is prefered. The vacume drops the boiling point of water way down. So the vac pump can suck the water vapor out of the system. I was in a hurry and very tired and connected the vac hose and it didn't depress the schrader valve very well if at all. I did not have the micron guage attached. And released the refergerant. After getting some rest i started second guessing if i had it vacumed sufficiantly. So to error on the safe side i recovered the refergerant and started vac with micron guage. Shrader valve removed 29 inhg was obtained quickly but 8 hrs later the micron level got down to 500 micron. Im assuming it took some time to dehydrate the moisture from the oil. HVAC is not my prefered line of work. I do it when required. Have most of the equipment to do it correctly. I do it when required for myself or friends and chillers at my employment. And have to refresh my memory when doing so. My point. Is if you have a micron guage avaiably. Use it.

[@buttercatz99]

Make a video that is simple and quick on how to use a micron gauge?

[@robertgregory2618]

Do you have to take the shrader valve out to use the micron gauge. I know it's faster but we are only checking roughly 30 feet total copper lines, liquid and gas lines.

[@joeybalogny6095]

great videos love them awesome you can use tru blu great thread locker awesome video thanks for the help.

[@pjtill1]

Do you put anything on the threads of the caps to help create a backup seal?

[@HVAC_Mechanic]

I use Nylog on the flares but nothing for the threads.

[@JoeNorsworthy-nm3bt]

What line should I open first Big one or small one

[@bradywassam5232]

Big

[@gilbertjaramillo8735]

My ac compressor and condenser have no refrigerant, so I need to do a pressure test on the whole system. Can I open the service hi and lo valves so the nitrogen can go thru both the compressor and condenser or should only the evaporator and its lines be checked? Same question to do a vacuum test? All the system or just the evaporator side?

[@HVAC_Mechanic]

If the valves are closed, it will only test the line set and indoor unit. Most leaks are in the line set connections, but they can be elsewhere. Basically, follow the manufacturer's manual to make sure the pressure doesn't exceed what is safe or components can be damaged. As long as the manufacturer's high pressure is not exceeded, it won't damage any components. After the leak is found and fixed, the whole system will need to be set in a vacuum.

[@gilbertjaramillo8735]

But I want the valves open to test for compressor and condenser leaks. Is it possible?

[@HVAC_Mechanic]

Yes, just don't go over the manufacturer's high-pressure rating for the unit.

[@kneedlezkane7665]

Awesome Thank you

[@johnmatasr1074]

Are the two-way valve and three-way valve closed when vacuuming the lines?

[@riotgear6891]

For the initial vacuum, yes. They are closed because they are keeping all the refrigerant in the condenser.

[@johnSmith-dl8eu]

does it matter which side the refrigerant is release to first?

[@HVAC_Mechanic]

Some manuals will state to open the low side suction line first (Big line), while other manuals don't state anything. Be sure to check the installation instructions or manual for the unit, but I don't think it matters much.

[@johnSmith-dl8eu]

thanks

[@byoung1520]

Does it have to get to -30? Mine gets to -15 but it will stay steady at -15

[@HVAC_Mechanic]

It depends on the vacuum pump how well it pumps down, but a slow pump should get to at least -30 Hg. Also, be sure to check the gauge is R410a.

[@JoeNorsworthy-nm3bt]

What line should you open first

[@HVAC_Mechanic]

Most manuals will say to open suction line first

[@burleypierce2999]

Do have that part number for the adapter? Thanks in advance

[@HVAC_Mechanic]

It is a 5/16" to 1/4" adapter. A link is in the description.

[@Iamkab]

When I connect my adapter to the service valve it starts shooting out quite a bit of coolant before I can even get it closed. I noticed yours did nothing like this. Why would that be?

[@HVAC_Mechanic]

During installation, there should be no refrigerant in the lines until it is released, which is the last step. Refrigerant is only released after the lines are in a vacuum. If refrigerant is in the lines, it needs what is called a Pump Down done first.

[@Iamkab]

​@@HVAC_Mechanicsorry, yes I am trying to do a pump down. That is when I'm experiencing this issue. I think the problem is I am not confident enough to just keep screwing it on as it shoots out

[@HVAC_Mechanic]

When shipped refrigerant is locked in the outside unit which is only released after the line set is in a vacuum. A Pump Down it is putting the refrigerant back into the outside unit as it was when shipped. There should be no refrigerant in the lines while placing the line set in a vacuum. A Pump Down and vacuuming the lines are two different things.

[@Iamkab]

Yes I am trying to do a pump down to move my mini split temporarily. The issue I am having is that it was shooting out quite a bit of gas when trying to connect to the service port​@@HVAC_Mechanic

[@HVAC_Mechanic]

Sorry, I misunderstood. Yes, the connections need to be done quickly. A small amount will come out, but it should be minimal. Be sure the equipment is good. It might help to watch a video of it being done.

[@crowderglen]

Thank you for the video but I’ll repeat what has been said before. Comparing micron gauges and analog gauges is like trying to measure 10 inches with your car’s mileage counter. Analog gauges just don’t have the fine resolution like micron gauges have.

[@gilbertjaramillo8735]

Thanks, I will use 150 to 200 pounds max.

[@BrianHsu-m2h]

The line set should not rolls so many,You should cut the tube make new flare connecting the unit for better oil return.

[@HVAC_Mechanic]

You can cut the line set, but it is not necessary. If the line set is cut, the refrigerant needs to be recalculated since the unit is prefilled for the 16-foot run.

[@salvatoregiovanni8967]

Good video, but you do absolutely need a micron gauge. Mini split manuals will specifically give a micron value to ensure a deep vacuum is maintained. Traditional Gauges don’t tell you shit as far as vacuum depth. Dish soap will only show the worst of leaks. Oftentimes a slow leak won’t even show up using dish soap. I still appreciate the spirit of your video.

[@HVAC_Mechanic]

Micron gauges are good but are not necessary; analog gauges work just as well. Many installers don't even use gauges or a vacuum pump at all and just do a line set flush. Soap will find small refrigerant leaks and is a common method to find a leak and fix a leaky unit. If you have a micron gauge, use it, they are good tools.

[@robertgregory2618]

Dakin and Goodman 12000 units don't suggest micron gauges, why do you think they don't suggest micron usage?

[@salvatoregiovanni8967]

I’m just saying it’s impossible to determine how well your system is vacuumed with an analog gauge set. Just for reference, the “29” on your gauge is roughly 23,000 microns. “29.92” is 50 to 100ish microns. Is your eyeball resolution good enough to divide the space between the 29 and 30 on your gauge (assuming it’s even calibrated) into 23,000 equally spaced tick marks? Almost all equipment manufacturers will recommend a 500 micron vacuum will be held for a specified duration of usually 5-10 mins for a system to be deemed “dry.” Any vacuum is better than no vacuum. So yes, your system will work if the vacuum is done as you suggest. Will the compressor life be as good, and will the system operate as well as one that has a proper vacuum done with a micron gauge? No.

[@robertgregory2618]

@@salvatoregiovanni8967 Thanks for your time making that response. Makes sense what your saying. May I ask one more question? Do you absolutely have to take the shrader valve out to add the micron gauge if you have lots of time.

[@waituntilthebeep]

The low side connection... the large line that you hooked the blue line to from the gauge set... when fully opened is called being "back seated" and the pressure that is on that blue line is ONLY freon from the valve to the manifold head. There is no reason to "remove it as quickly as you can" to cap it. If that valve is opened until it stops, it will not leak out freon from the system. Remove your blue line and install the cap that came with the system. All is well. When vacuuming the system down, both of the valves should be closed and the only part you are putting under a vacuum is the line set through the evaporator (inside head). Once under good vacuum, opening both the valves fully closes the gauge set off from the condensor and prevents any freon from leaking out unless you have a bad flare on one of the lines. People think HVAC is scary. Fortunately sellers like Senville and all the others (made by the same company BTW) make installation pretty easy. They also make HVAC repair people

[@mikafoxx2717]

Can't believe nobody else talks about pumpdown if you do have a leak. Damn. I was considering using a can of legally ventable R-290 to check for leaks before final pumpdown but this makes it much easier.

[@HVAC_Mechanic]

That is a good idea, and what some installers do is use an eco-friendly refrigerant to test for leaks before vacuuming down the system.

[@JoeSevy]

5000 microns is about 29.72 on the gauge. 1000 microns is about 29.88 on the gauge. 500 is about 29.9. 110 is about 29.92. The difference between 5000 microns and 200 is just barely perceptible if you're using an analogue gauge. And you will NEVER drop under 2500 microns if there is water in the system and you'll NEVER be able to tell the difference unless you're extremely observant and have pulled vacuums many times. If there's any water in the system it will look exactly the same as a good vacuum on analogue gauges. Using an analog gauge is slightly better than no gauge at all. A leak that loses 500 microns won't even register unless you never got a decent vacuum in the first place. The cheapest micron gauge is better than the most expensive manifold gauge set. Invest in the correct tool for the job or you're really just counting on being lucky. You can get a TPI Gauge for $110 You can get the Fieldpiece VC2G with the 5/16 adapter for $150 You can replace a ruined system for two or three grand. You can do a proper install without a manifold set. You cannot do it without a micron gauge.

[@HVAC_Mechanic]

Micron gauges are good if you have one use it; if not, analog gauges have been used for much longer and also work very well. Either will work.

[@JoeSevy]

@@HVAC_Mechanic That's a bit like using analogue phone tools for computer networking. Some of them might still be relevant. But you NEED the relevant tools necessary for modern equipment. IF you can guarantee there's no water in the lines, IF you purge them sufficiently and leak test them, say, overnight for both pressure and vacuum, then maybe you'll do an adequate job. But, you'll never know if you did the job correctly or not unless you use a micron gauge and conduct a micron decay test. You simply can NOT use an analogue gauge to see what you need to see. It simply doesn't have the resolution. A system with a tiny bit of water in it will look exactly the same as one that doesn't. But, it won't last as long. About all that gauge is good for is discovering relatively huge leaks over a relatively long period of time.

[@HVAC_Mechanic]

The process has been the same for 100 years; no new tools are needed. Many installers don't even vacuum the unit down; they flush it with R153a and tighten down the lines while it is under pressure. This argument over micron gauges reminds me of the new auto mechanics fresh out of school who can't troubleshoot without a scan tool. In the end, to each their own, whatever works to get the job done.

[@JoeSevy]

@@HVAC_Mechanic I have a toaster I use regularly that is 98 years old. Like any toaster made in the modern day it heats bread to make toast. I can NOT use my knowledge of how it works to repair a toaster made today. I have explained why the method you're advocating is inadequate to the job you're doing, and trust me on this, I absolutely understand that you're motivated to believe the work you've done to the best of your ability with the tools you have is first rate work, fully the equal of anything done by anyone with their fancy shmancy modern tools, and I even agree it might happen to actually BE equivalent to anything done by 'technicians' using the latest tools. What I'm trying to point out is that, even though you might not see the evidence directly, it wouldn't show up directly. A system lasts ten years when it might have lasted fifteen isn't something you have the ability to see without quite a lot of data which would be really hard for you to collect and analyze. It's completely natural to suppose that anyone leaving contradictory comments to the information you're providing is simply trying to tear you down, to attack your credibility and diminish you. And, maybe most of the time that's exactly what's happening. That's not what's happening here. You are unquestionably a smart guy who wants the people who watch your videos to become properly informed, not to chase clout, not for status or a few bucks, but because you genuinely care whether or not the information you give them is accurate or not. Look at the objections I've raised, specifically. Don't imagine I've said something I didn't. Look at the actual technical claims I've made. Where am I wrong? When you say the process has been the same for a hundred years, that's true in an overall sense. But the technology has evolved. We're not dealing with the same refrigerants, lubricants or materials. As to HVAC techs using refrigerant to flush the lines... can't say as why that wouldn't work... for them, not for people without access to the refrigerant, and in any case isn't what you're teaching people to do. Bringing up automotive scan tools points out a very similar thing. Such tools are a necessary but not sufficient means to diagnose modern cars. Old cars didn't have a MAF, a MAP, oxygen sensors, computer controlled fuel trim or a hundred other things to consider. Other than through sheer luck it is actually impossible to diagnose a modern car without the correct tools, and a 'scanner' is absolutely the bare minimum necessary tool which most of the time just minimizes the range of guesses. I am absolutely certain you don't want to get this wrong. So, examine what I've said and decide if there's anything wrong with it. Watch this video and tell me you're actually certain the setup and methods you're using sufficiently deal with the problem. kzbin.info/www/bejne/hp6bnnV5ga9nb9ksi=Np4clkmHwBE_8DSC

[@HVAC_Mechanic]

I have installed many mini-split and standard split systems that are still working 20-plus years later with no issues with using an analog gauge. I have two-micron gauges and use them, and while they are good when working, they can be off sometimes. I've seen several installs messed up when the installer's micron gauge gave bad readings. Many installers these days are moving away from using a vacuum pump and don't use any gauges they use a flush like KWIK-E-VAC. Most new techs use micron gauges or the flush method, while 15-20 years ago, there were only analog manifold gauges. I guess I'm old school. In a few more years, analog gauges will probably no longer be used, but they do work. I've been using them my whole life.

[@JoeNorsworthy-nm3bt]

What line should I open first Big one or small one

[@blunismo1]

I would presume the line that has the service port on it.