Dry nitrogen high-pressure decay test using Fieldpiece SM480V

[@Automotive_Solutions]

Nice setup and great info. Thanks 👍

[@HVACRCERTIFIEDTRAINING]

Hi

[@HVACRCERTIFIEDTRAINING]

Hi ,nice video! Keep going doing great content

[@mike-yp1uk]

Very good info. Thanks

[@romonek]

You did not hook on the suction line temperature clamp for the changes in temperature and pressure of the nitrogen. With out that u'll never know, especially if it's a small leak with the change of temperature of line & nitrogen.

[@coldfinger459sub0]

Do not need the temperature clamps for the short duration pressure decay test. The temperature in the shop or the car is not going to change within three or four minutes. Sometimes reading or just being a smart or listening to a KZbinr I t’s not a good thing if you don’t know the whole story Do you have to have a firm understanding of the physics and science hind your tool and process your performing to know what you can and cannot do. And using the temperature clamps in some scenarios can get you into big trouble giving you false data if you don’t understand the physics and science on how they work. On the type of equipment that you’re diagnosing have there’s a unique scenarios that can set you up for trouble if you just listen to a tool a tool is only as smart as a tool that is using the tool.

[@ES-iv6wb]

Amazon video, super impressed. Subscribed.

[@ES-iv6wb]

I just got a lightly used SM480V and I’m testing it on a bottle of nitrogen, to make sure the manifold or hoses aren’t leaking. I hooked up high side to the tank at around 170 psig then removed the hose, and let it hang. Then I did the same thing on the low side. Starting pressure for both was around 167 psig. Within an hour both my high and low are around 150 psig. I tried using another set of hoses, and I get the same issue. Is my manifold really leaking?

[@coldfinger459sub0]

@ES-iv6wb retest. Put it up to 200 psi if you can . And then let it sit with a Valve open at 200 psi do not start your test yet After 15 minutes . Close your valve to your nitrogen.. After about another five minutes now, start and press your button for your nitrogen Decay test . Give your hoses time to expand as well because of the high pressure in the hoses there slowly moving Give your nitrogen in the manifold and the hoses to adjust to the temperature if there’s any difference from when the tank to the hoses. And retest And you can spray or squirt or tab on some soapy water or leak test solution. On all your knobs engages, you can take your knobs off by removing the Phillips screw in the center of the plastic knobs.. They pull straight out While you have 200 psi, you can spray or tap on your leak bubble test solution. If you see no leaks around your vowels all your site glass, you have no leaks there.. Now you can start checking your brass cramps on your hoses and the seals around in Fittings on both ends. Let me know how your test come out

[@ES-iv6wb]

@@coldfinger459sub0 thank you! Will retest and let you know.

[@ES-iv6wb]

Initially I did this test at 170 psi, bc I wanted to test an inficon ultrasonic leak detector that I bought. I saw a mixed bag of reviews on ALL of the ultrasonics out there, and wanted to see for myself if it worked. I couldn’t find hear a leak on the inficon lol. Is there a good product on the market that can detect high nitrogen concentrations (I know air is mostly N2)? The reason I ask is I don’t like to load the system with refrigerant to check for leaks. Any other solutions?

[@coldfinger459sub0]

@@ES-iv6wb ultrasonic works good it will find certain types of leaks that you may not find otherwise. With other types. Refrigerant leak detector will find leak ultrasonic may have hard time finding. Then sometime UV finds types of leaks both others will not find. Another time soap bubble can find the leaks you missed with the others. Ultrasonic can find vacuum leaks . No other can do that. Ultrasonic thanks a learning skill. High frequency, bounces off of hard objects, a directional.. if you don’t understand the physics in the first place, how are you going to use it properly if there’s nobody to teach you. You may find extension cord very close to you after the power with interference that you were here on a shop light that you may be using . So you will have to move that out-of-the-way LED and some fluorescent power ballast give off radio interference that it may pick up . So you might have to turn off the shop lights or move to a different location . Or use an old fashion incandescent light bulb in your area.. People will have problems with ultrasonic because they have no education on it to use people think you just pick up at all and use it and it just works. Doesn’t always work like that. . The same thing there’s a difference in the way you use a heated diode leak detector sensor compared to a infrared detector sensor . And they will get some mixed results. Some bad results frustrating results because they’re an educated on the equipment. This is the problem with a Automotive Industry.. there is no mandatory formal education required. Like a 4 1/2 year program I went through or four year apprentice system. My father went through and going tonight classes at night time learning all the stuff. We have a nation of ignorant retarded people who are allowed to leave the schools no longer have auto shops and other trades classes. High pressure nitrogen works excellent Only problem thing comes back to education People are not talked that certain types of leaks only leak under certain types of situations. They are not all constant. They’re like pressure pop off valve some of them. Some leaks will only leak in the middle or the rubber hose gets cold and then when you turn off the AC system leak stops Some leaks only leak when the system is hot with a hot high-pressure refrigerant system is turned off and leak stops Some leaks you’ll find only leak at low pressure . As soon as you start, putting in the refrigerant after you completed all your leak test, you will add the refrigerant and all of a sudden you will hear a hissing sound from a loud large leak.. And you will easily find a leak. But if you start the system up and make a high-pressure, Earl get hot Tahlequah stop.. and then you go shut it off and you look for the leak and it doesn’t come back. I didn’t mention all the ways leaks happen, only some of them . So how can you find his leaks with any of those leak detectors? They won’t find out because at the moment that you are testing leak is not happening . Can you have what is called forming gas? It’s a mixture of 95% nitrogen, and 5% hydrogen or 5% helium depends which one you purchase And you have to purchase a special leak detector that has only meant for hydrogen or helium . This method you get the best of both worlds Because you could pump up the system to 200 psi, and look for the leak with an ultrasonic leak detector and a dedicated helium or hydrogen leak detector and soapy bubbles. So this type of lease detection gives you three methods using forming gas. 3 in 1 UV dye finds some of those hard to fine lakes that happen weeks later or months later days later. Or the leaks that only happens when the car is going down a rough road and the hose is bouncing around and it starts leaking at the crimp connection But when the car is still in stationary in your workshop with a hood open, they don’t leak .

[@hroberts9064]

I just stumbled on your videos today - your knowledge and experience on automotive HVAC is impressive! I'm changing the evaporator on my 1990 Infiniti Q45. My Fieldpiece SMAN is showing a pressure differential of -0.6 PSIG over about 13 hours (sitting overnight) with an initial fill of nitrogen at about 145 PSI. For the first 2 hours, it showed no drop at all. The ambient temperature dropped about 8 degrees because I was cooling off the garage overnight with a portable air conditioner, but the SMAN is supposed to compensate for that. I had the temperature clamp on the low side pipe near the evaporator. Do you think this is a significant leak?

[@coldfinger459sub0]

It’s probably not a leak. If you leave it on for the next day. If the temperature towards the end of the day gets to the same temperature where you started your test, you’ll probably see that 0.6 go back up. . To 0 If you did not see anything in the first two hours . It did not move at all. And then buy the next morning when it got cold it went down. I’m gonna blame it on the temperature. . Now you could leave it on the vacuum pump for 24 hours . You can never over vacuum.. especially on a car that old. All you can do is remove more moisture.. which is a good thing. 👍 Congratulations on your SMAN

[@hroberts9064]

@@coldfinger459sub0 Thanks for the quick reply! I'll try another test without the air conditioner on to keep the temperature more constant. The long vacuum is also in the plans, since I'm going back with R12. 😬

[@komoru]

On the newer r1234yf systems are you still going to 150 psi when you pressure test with nitrogen or are you testing with higher pressure? Prior to watching your videos I had been doing testing to 250 psi to test ac systems, but 90% of the cars I work on are classic mercedes with r12 so the components are pretty beefy.

[@coldfinger459sub0]

On the 1234 I do at 170 psi

[@ElTexMexAlex]

For the nitrogen leak test, do you use the co2 sensor with the inficon stratus?

[@coldfinger459sub0]

That is something I’m just starting to do for some test. I want to see the difference capabilities of what size leak a refrigerant leak sensor finds Compared to CO2 on the exact same leak. The common every day package CO2 is considered usually a dirty gas that sometimes has contamination of moisture. So it has been often advised not to use it in a system that contains POE oil or PAG oil because it loves to absorb moisture. You either have to buy and go out of your way to purchase laboratory grade or medical grade CO2 to get clean pure CO2 Or you could run it through a filter dryer yourself slowly to remove The moisture content and then run it through a moisture indicator so you can actually see the reduction in moisture removed. Do you also want to take a CO2 tank and put it on a vacuum pump and get it down below 100 µm so you know the actual brand new tank that you will be using is moisture free and air free of contaminants. Then do your CO2 transfer throw your new tank into a freezer it helps if your new tank is colder than your supply tank CO2 is extremely reactive to temperature and pressure changes.

[@cathayvillagecondominium6343]

What’s the fitttings and adapter you use for sm480 to hook on to car ac system. Do you have a link to buy? Thanks

[@coldfinger459sub0]

Sorry no link. You’re just looking for fittings that have quarter inch thread is a common thread size on HVAC hoses.

[@moebassidji8306]

what pressure drop will make you look for a leak in thightening test mode?thanks.

[@coldfinger459sub0]

First when you’re performing a dry nitrogen high-pressure decay test. For example you fill the system up let’s say 170 psi pressure through the tank of nitrogen. You now shut off your valves to the nitrogen tank Then you let the pressures stabilize for five or 10 minutes first before you start your test. ( because there is a period when you first fill up the system the gases are heating up or cooling down depending on temperature differences and things like hoses are stretching) Now you hit your button for tightness test after you have waited for the system to stabilize. After 10 or 15 minutes you probably should not see more than two or 3/10 of a psi drop and then it stops moving. Now if it’s a very hot day and the Engine is hot and the interior is hot you may see the pressure go up. A few tenths or a psi because if the tank of gas is only 80°F and you push it into hotlines hot evaporator with a hot interior that’s 140°F the gas will increase pressure a little bit The same goes if the tank is hot and you put it into a car that’s sitting outside overnight on a cold night in the car is 40° you will see the pressure go down a little bit but then stop when it equalizes. For those very small leaks if you see two or 4/10 of a psi after five or 10 minutes. Leave it on for another 10 minutes. Did he drop another 4/10 ? When you have probably a leak. Leave it on for another 10 minutes did I drop another 4/10 or 3/10 now you can probably say you definitely have a very small leak somewhere And this is where the ultrasonic leak detector finds those type of leaks because it’s not refrigerant it is dry nitrogen.

[@moebassidji8306]

@@coldfinger459sub0 i appreciate the knowledge passing to us. Thanks.

[@AG-tg9in]

Your actually using the trublu hose the wrong way. Might as well just hook up the regular 3/4 hose. And when you do microns you gotta do less the. 400 and if it passes the 1000 mark then you gotta problem buddy. I do commercial hvac and mainly refrigeration. But nice video spreading the knowledge 🤝👍

[@coldfinger459sub0]

Yes I actually tell in some of my videos you should not use the true blue hose with refrigerant hoses because you basically defeat the purpose. Because you’re only as good as the weakest link and even if you use the metal pipe from your vacuum pump to your refrigerant manifold and had the possibility to draw down to 1 µm at that point only. You would lose 99% of your benefit as soon as you go through the refrigerant manifold with all its O-ring seals and connections and those horrible refrigerant charging hoses that leak like a sieve. refrigerant manifolds are often contaminated with POE oil or PAG Oil with tons of moisture in the refrigerant hoses. I gear this towards the automotive guys because I know unfortunately they’re usually lazy and some of them are cheap and then there’s the ones who just don’t care or want the quickest easiest cheapest method. That’s why I show them this method For the guys to really pay attention they see my videos where I take the true blue hose directly from the vacuum pump right up to the refrigerant lines of the vehicle with no manifold direct connection. Able to pull some of the vehicles under 100 µm which is not easy especially if they’ve been contaminated. I myself sell the LG multi V VRF Systems my son and I do the installations. In those cases when I wanna go overboard I don’t even use the true blue hose I use soft copper refrigerant line as my vacuum hoses. This is what my dad taught me when I was a kid using soft copper instead of hoses and this is what my dad was taught by an older gentleman in refrigeration.

[@AG-tg9in]

@@coldfinger459sub0 my fault for that. So how you had the trublu hooked up what different do you get then the 3/4 from another brand?

[@coldfinger459sub0]

@@AG-tg9in you cannot pull a slow vacuum through other refrigerant brand hoses that were meant for refrigerant then you can a silicone hose. And if you attempt to use the hoses to hold your vacuum the hoses themselves off gas and lose vacuum. I know I did some videos before where I switched out large diameter refrigerant hoses for a true blue hose showing the difference in vacuum polled just by switching that one hose. I also showed a video where I remove the refrigerant hoses and use soft copper lines for refrigerant hoses I believe they pulled a vacuum down below 10 µm in that video. For deep vacuum this was the method my dad showed me as a child more than 40 years ago. Using soft copper as lines with something that was shown to my dad by an older refrigeration gentleman. Using soft copper or stainless steel in Laboratories has been around forever it’s an old method old technology it works better than anything else it’s the cheapest thing to use because we all have scrap copper. And it works the best. But I did a series of videos I believe on Fieldpiece gauges that were brand new swapping out different refrigerant hoses using a micron meter on showing the difference in performance. In a few of the videos I even use the BluVac Accu tools micron meter with the software data logging the vacuum over night pulling down below 10 µm and then data logged the vacuum decay over a 10 or 12 hour period of time. In my progressions of videos using different poses in different upgrades you can actually see the evidence by the measurements by the micron gauge of improvements.

[@BERESHIDA2008]

@@coldfinger459sub0 how long ago was that video u mention?

[@coldfinger459sub0]

@@BERESHIDA2008 I found one of them this is number for video so there’s some videos before this one and there’s several videos after this one they’re kind a spaced out kzbin.info/www/bejne/a6XFgWN3obiHZ5Y Periodically I released videos about refrigerant manifolds and testing them specifically showing why it is not a good idea to use refrigerant manifolds when you’re trying to pull a deep vacuum. But when you’re learning and you’re starting and buying a whole bunch of components is out of your budget you might as well start with a good refrigerant manifold that has a micron meter built inside so you can at least get a general reference of how it works and learn how to look for problems even if it’s your own hoses your own gaskets or connections that are causing the problem. Fieldpiece SM480V. It’s about as good as you’re going to get for an excellent starting point. www.trutechtools.com/Fieldpiece-SM480V The link above takes you to an Internet tool sales place that just specializes in air conditioning tools this is where I get my air conditioning tools from

[@bgpobeda]

Vacuum pump, which brand and model is?

[@coldfinger459sub0]

www.trutechtools.com/NAVAC-NRD16T-Industrial-Vacuum-Pump-12-CFM

[@coldfinger459sub0]

NRD16T NAVAC

[@markhoffmann5941]

12 CFM pump!!! 4 to 5 CFM 16ton to 25ton (Typical Residential A/C System) would require a pump with a 4 to 5 CFM rating. 16ton to 25ton (Commercial Systems) would require a 6 to 8 CFM rating.

[@coldfinger459sub0]

@@markhoffmann5941 time is 💰 money 💸 It all depends on how fast you want to get there and how low you wanna go Compare to residential and commercial automotive HVAC systems are completely an entirely often moisture contaminated very heavily. Automotive technicians when they work on any part of the system often just leave the exposed lines open to the air for hours days and in body shops even months waiting for Parts. There is no education, Automotive industry that is mandatory or required Many professionals or just learned by breaking customers, stuff and learning. They were taught to use shop compressor. You know the stuff that has all the water squirting out the end of the hose to squirt into the air conditioning system to pressurize to look for leaks. You might as well take a hose and do a hydrostatic pressure test We’re talking about some of the most uneducated individuals in the history of mankind Just because education is not required to be an automotive technician. And the model is it works it blows cold on your hand therefore it must be correct 🤦‍♂️

[@stephang9588]

So was there a leak on this car ?

[@coldfinger459sub0]

Yes there was a leak because it came in with no refrigerant in the system but just not a large leak that could easily be found. That was a year ago so I don’t quite remember what the final outcome is either I found a leak after I put refrigerant in it or did not. Many times you could have leaks that only leak at a certain pressure or temperature when the refrigerant gets hot on the high side or cold on the low side and it only leaks at that point but it doesn’t leak while it’s just standing there in front of you under ambient static conditions Some leaks only leak when the vehicles driving down the road vibrating as it’s moving but does not leak when it’s sitting still in the garage operating.

[@stephang9588]

@@coldfinger459sub0 okay thank you . But the gauges indicated no leak ?

[@coldfinger459sub0]

@@stephang9588 exactly. Proving that all leaks do not leak all the time even though you know there’s a big leak. Some leaks only leak when the car is going down the road vibrating when components like hoses are shaking and vibrating from the lumps and bumps in the roads Some leaks only leak for example the high side refrigerant line starts getting hot as the air conditioning system is in an operation on a very hot day and every time the pressure gets above for example 200 psi the leak opens up and starts leaking and release some of the refrigerant but when you shut the car off The leak stops leaking Some leaks only leak when the low pressure low side of the system starts getting cold in operation and the temperature starts approaching 30°F in the middle starts shrinking and it opens up a crack starts leaking out refrigerant but as soon as you turn it off in the middle starts warming up instantly it seals back up and stops leaking And there’s so many more different scenarios in which a leak can happen and then completely stop and seal up under a different operating circumstance. And this is one of those examples we are sitting static in a garage applying pressure it doesn’t leak but yet there’s a big leak somewhere that will only happen under a certain operating condition this is what makes finding leaks so difficult. So in this scenario this car is a good candidate that when you put in the fluorescent UV dye. Can you let the car go back out in the road and use the air conditioning like normal for a few days a few weeks or a few months. And after that time when we’re turning where the leak happens hopefully the UV dye came out with the refrigerant in the oil and left a small stain to be visible that the UV light can pick up and see.

[@bobbyanderson2168]

Dude, you should always pressure test with similar working pressures. You should not pressure test s 410a system with 80psi. You ain’t kidding about the vacuum seals. A deep vacuum will easily pull IN a schrader. You can have one on a filter drier or for discharge pressure, rite off of the compressor w/out a cap. Or a loose cap. And just murder your vacuum. Bro, you got a leak there. I think your pressure is good. You need to let it set longer. I would TRY more pressure tho. I don’t work on cars.

[@coldfinger459sub0]

That Prius on the automobile I was pressure testing at 152 psi with dry nitrogen that is its working pressure. I also do the large LG multi-V VRF 20 ton to 60 ton unit installations with 1000 to 3000 feet of copper pipe that I sell and install myself with my son. On those units we use a dry nitrogen high pressure decay test at 600 psi for 24 hours. Usually I like to try to perform my high-pressure dry nitrogen decay test starting on a Friday leaving over the weekend and coming back on on Monday so it has two or three days to determine if there’s a leak. And all the time I’m grafting it on the datalogging program following the rise in the fall of the nitrogen pressure as the nights get cold and the days get warm and every day the nitrogen goes back up to exactly where it was when you first installed it at that particular ambient temperature.

[@8799crosby]

you realize a car runs 134a not 410 a way less pressure on 134a

[@coldfinger459sub0]

@@8799crosby that’s why I only pressure test them out 150 to 170 psi Because that could be the possible maximum temperature of are 134 on a hot summer day with a car with a hot engine sitting out on the blacktop parking lot in Arizona on 115° day with an inside cabin temperature of 140° and an engine compartment temperature of 240° Using the highest possible evaporator temperature the standing static highest pressure can possibly be roughly 230 psi don’t wanna go any much above that with risk of damage to the evaporator‘s because they were not designed to go much above that.