How to Leak Test an AC With Nitrogen Pressure

In another one of our animated air conditioning how to videos Bryan explains How to Leak Test an AC With Nitrogen Pressure.
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[@evertvalencia920]

I love the way your teache , I wanna know more about A/C and Refrigeration, thank you

[@DanO181919]

This is one of the best channels to learn on. Another good channel is AC Service tech.

[@rajendraenglishclasses6465]

Great ways of explanation

[@marcdorizar5742]

@@DanO181919 another great one is word of advice.

[@DanO181919]

@@marcdorizar5742 yes, I’m subscribed to that channel as well. 👍🏻

[@simplescrapping]

Greetings from Greece😃. I'm a hvac technician and I have watched all of your video. I have to say that I learned (or understand) a lot of things. Keep the good work😉

[@craighvac1808]

Never knew what a hard shut off Txv was, seen that happen many times pressure testing splits. Thanks for the info!

[@osamajassim5204]

Excellent way of teaching,god bless you.

[@ardichico205]

your video is the best one i've came across, ive been looking for 2 or 3 days, yours is very simple , straight steps that didnt go over my head or confused me . Thanks !!!!!😁😁😁😁🙌🙌🙌🙌

[@fawzannn]

Thanks for a wonderful explanation

[@kwj21st]

Thanks for the useful video.

[@devbella5223]

Ahh wow lots of good info here- I love the core tools and the probes… less leak points this is great- need to save up for some probes, just ordered a testo 550s hoping they’re good

[@michaelstaley9979]

Great video.

[@halleffect1]

very good info, thanks

[@AutoTechWorld_DIY]

That was a well made video. Thank you

[@Vore667]

Excellent. Thanks!

[@gadgethunter5732]

I would add . Even after recovery to prepare for a pressure test , the system will have some refrigerant in it . Do a quick pressure test to eliminate any huge leaks . Purge the system. Pull a quick vacuum to try and remove some of that residual refrigerant { in the compressor oil etc } The extra residual refrigerant will mess with pressure /temp swings way more than just nitrogen. And for you new guys that might have just glanced the part about a 600 psig test pressure, thinking more pressure is better ? Remember, a compressor shell can experience tons and tons of pressure on its walls. Add too much pressure and it can become a bomb. Going to extremes on pressure testing can become deadly.

[@charliewingard6244]

Thanks!

[@sunimalfernando4347]

Thank you!!

[@MarcinDrozdowskiMMM]

Very valubale. Thank You.

[@eugeneb3682]

Thanks

[@LongTrout]

Thankyou for the advice on the Schrader core leak test...Been doing this of and on since 1985 and still didn't figure that one out . My father taught me that if it leaks under high pressure it will leak under low pressure......Wouldn't nitrogen test at 75 lbs be just as effective under soap bubbles to the discerning eye....Nitrogen gas is a fairly small molecule and would leak more readily as opposed to cfc, hcfc, or hfc...

[@davids8133]

Question unrelated to latest video: What temperature difference if any can be expected on a gas furnace in heat mode across the a/c evaporator coil?

[@huntercovington9421]

Sman 480v has a tightness test that accounts for temp which is nice

[@genepierson1728]

Do you need to pressure test on both the highside and lowside scrader valves?

[@raymondlaine9617]

Who/how are you making these animations? Love it.

[@MrMelo313]

Do you have to pump the system down/remove all refrigerant before nitrogen testing? Does it also need to be vaccumed after everything?

[@danleitner1635]

What brand of core removal tool, with side port, do you recommend?

[@kevinvega1572]

When adding nitrogen for a leak test do you guys recover all the freon before adding the nitrogen or do you add the nitrogen with freon in it

[@kirill26reg]

Спасибо!!! thanks in russian!!!

[@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?

[@whitesheatingairappliancer7101]

Did big blue change there product? I bought a 1 gallon jug to refill my spray bottle. I noticed the new stuff is thicker. Nothing on the jug says to dilute it.

[@ChuckBaggett]

Can at ultrasonic detector detect dry nitrogen? I see some advertised as doing so. An AC tech said they can't, but that might be because I suggested it. Also, nitrogen lets you use soap bubbles, hear it, and anything else.

[@swamiadharpanda3646]

Saluting you sir

[@frankduarte7109]

How long do you purge the lines for before pressuring the system

[@Armikrizaful]

Nice video, is there any standar for nitrogen pressure for leakage test?

[@tonyp6088]

Hi there, that is a really good question and I'm surprised it wasn't covered in this video given that's the most important part. The answer is the test pressure should be 63 degrees Celsius saturated temperature of the refrigerant used. For example if you are using R134a 63 degrees is approx 1700kpa. You you would not pressure test above that. And for the low side of the system it is advised not to exceed 45 degrees sst. I hope this helps someone. Remember different refrigerant operate at different pressures. The pressure test needs to be at the highest operating pressure which is 63 degrees Celsius. (High side)

[@cj691]

That is a Victor gauge. The Western HVAC regulators have fixed test pressures.

[@sterlingarcher46]

For us Europeans it blows our minds that you lot are still using freon as a tracer gas , we stopped doing that years ago because its sooo forbidden ! We use Trace-a-gas which is a mixture or 95% nitrogen and 5% hydrogen, then you just use a hydrogen electronic detector and voilà. And now they make electronic leak detectors that react to HFC , HFO and hydrogen so you only really need one leak detector which is very handy. There's really no reason to vent refrigerant anymore to be honest.

[@tonyjr9757]

We use trace-a-gas too - for strength, pressure and first leak check all in one, then to OFN for triple evac. Hydrogen being the smallest molecule should reveal the smallest of leaks.

[@djguyvah8769]

Great

[@rhumzalicante3822]

Can i use SCBA(Self Contained Breathing Apparatus) instead of Nitrogen tank? For leak test

[@user-vy2sx9hn1x]

I have one question : What is the less purity of Nitrogen we must use for leak testing ???

[@soleilsoleil8287]

suuuuuuuuuuper vid.

[@markfowler9692]

Soooo what about Mini split systems - Only one evacuation port on the Suction line... Please explain how to do this on Minisplit systems...Recently started following your chnl, if you have already addressed this then please send me to the video etc...Thanks and love your videos !!!!

[@justinrichard4190]

the liquid and suction is basically a loop, you only need one port to add pressure, i usually go around 500 lbs on mitsubishi. then bubble check every flare, i usually bubble test then go around and hit them again before i wipe them off.

[@Papasquatch73]

Depends on the size mini. A lot have two ports

[@Howie875]

If you pressure test a system without having the service valves front seated, you will introduce this high pressure to the inside of the compressor shell, which is normally the low side pressure when it is running or equalized pressure while it is off .A 410a system can have pressures at the discharge line of over 500 psig when it is running, but this is not the pressure that the compressor shell is ever exposed to. There would be no problem with the heavier duty semi hermetic compressors but a thinner hermetic compressor could rupture under these pressures. I used to pressurize systems to 400 psig all the time until I read some information from Copeland compressors that ( from what I remember) recommended a maximum of 200 psig on the old R-22 compressors. May be higher for the 410a systems but I think 600 psig is excessive . You might want to recheck that.

[@jeffb8437]

I believe it’s 350 psig max on the compressor shell R22 or 410. The weld around the shell and terminals being the week links

[@sqeekykleen49]

Most have a plug in the bottom of the comp shell. When exposed to extreme heat as in a wildfire/grassfire, or structure fire this rupture disc expels an instant cloud of refrigerant and almost all of the oil in the can. Seen a few, very scary for g public.

[@sqeekykleen49]

Some pop the disc where the leads connect.

[@Howie875]

@@sqeekykleen49 In the larger commercial equipment I have seen fusible plugs that will turn into a liquid form and blow the charge at a predetermined temperature in case of excessive temperature and I have also seen pressure relief valves that are actuated at a certain PSI which is always higher that the high pressure switch rating for that particular unit. Was once silver soldering on a flat circuit on a dual circuit unit and inadvertently let my torch get to close to the fusible plug on the other circuit which caused it to melt and it released the molten metal and a stream of liquid refrigerant right at my face. Was lucky enough to somehow walk away unscathed from that one,

[@rajarmk8850]

Indoor or out door split AC checking pressure 380 it's wrong or right

[@kevincowan7131]

What is the allowable drop after an hour ???Say you pressurize the system with 250 what is accessible ?75 degrees??

[@Vikis42]

Sir ham 600psi peresure dety hin par suba kam hoa hota ha 560psi leakg b nhi ha ...kia masla ho skta ha

[@johannesvangalen2300]

Do you use dry nitrogen? If so where can you purchase? Thanks

[@tonyruiz2046]

HVAC supply distributors and welding supply distributors carry the dry nitrogen tanks and pressure regulator that you'll need.

[@80SWoods]

Do you have to use Nitrogen gas to pressure test? I’m installing my own system and have welding tanks on hand which are argon/O2 which have the same attachments as Nitrogen. I’m thinking that once you’re done testing and open the lines to vacuum pump, any Nitrogen has leaked out anyhow. Do you think it matters?

[@bryanswanson5007]

Nitrogen only

[@keithosterkamp6207]

In the presence of any moisture CO2 in your weld mix will form carbonic acid and you don’t want that circulating in your system.

[@astromaddox1989]

Do I leave the nitrogen tank open while waiting to see a pressure drop

[@johndoe-zz1nr]

How much the test should cost

[@Jeff-Lawrence]

I’m might be missing something but this got me thinking... the flow is cut off at the compressor and if so how does the air get purged between the high side service valve through the evaporator to the compressor or the low side service valve to the compressor. Just wondering

[@Oldthesis]

There is a complete circuit through the line-set (liquid line and vapor line) back to the outdoor unit, any air would be purged by pressurizing either side. Here, they show the liquid line pressurized first, which is typically the direction of refrigerant flow in the cooling mode.

[@Joy-tb1cp]

And how is a leak fixed if one is found when nitrogen pressured?

[@brianodental1634]

Jb weld

[@chrisE815]

Flexseal

[@mikecastillo5941]

Question for all you intelligent HVAC people . What is the Max pressure you would pressurize a new lineset with a new condensing unit with charge behind the service valves . Would you worry about forcing nitrogen into the condensing unit with to high of testing pressure ?

[@Wpg204wpg]

I always think about that .especially if I'm pumping down to leak search . Those valves always tend to have trace refrigerant in them .

[@ffrgdert540]

Hi, can anyone here let me know if its ok to charge r22 to a converted 407c system? I have a old r22 walk in cooler that was changed to 407c changed compressor . But there was a small leak, and the tech charged r22. Please let me know if that will cause a issue to the compressor. Appreciate your reply.

[@sambaron1319]

No! R22 is mineral oil. 407c is POE oil...

[@knutrichardvanderloock7914]

Is there a reason why you are using nitrogen? Can I use co2?

[@Bryan-Hensley]

Never ever ever ever ever ever put more than 350 PSi in a system. The compressor shell is rated around 350 PSI. The shell is never exposed to the output pressure of the compressor. 33 years experience working on heatpumps.

[@achempel46]

Copeland says 150psi

[@merckxherve9116]

Daikin ask 725 PSI for warranty in Europe. 350PSI is to low for detect very small leaks.

[@213BRANDONP]

LOL you're all right and you're all wrong one size never fits all just follow the manufacturer recommendation I assure you they know what it can handle

[@213BRANDONP]

@@achempel46 unfortunately it's usually not feasible to go off of Copeland's suggestion of course they don't want any load put on their compressors but if the system operates at higher pressure and they're telling you to test for the test on whichever pressure is higher Copeland also recommends no less than 20° super heat but good luck finding a manufacturer that agrees

[@213BRANDONP]

Myself I always just go off the low pressure max PSI stated right on the plate

[@janibashamolla]

Thanks a lot sir 👍👍 you explains very good but too fast talking...

[@MrSprintcat]

Don't put the r410a in as vapor you will screw up the whole 30 pound jug

[@pedrocastano6410]

I would like to know why, not questioning in a bad manner, just would like to know what happens to the rest of the refrigerant, if you c an explain. Thank you

[@MrSprintcat]

The 410 a is a blend . Needs to go in as a liquid. If you put it in as a gas it will screw up the whole blend .😮

[@glennhendricks4111]

Will someone help me understand how to nitrogen purge, test, and vacuum the Entire system....... inside unit, line set and( THE OUTDOOR UNIT ) of a mini-split with only one service port? Seenville 12,000 btu heat pump. The system is 6 yrs old, was given to me with no refrigerant in it. The owner let me have it for free. He said the only problem was leaking flares. He hired a cheap guy on craigslist to fix it.....well the guy supposedly lost the charge and never came back to fix it. Professionals wanted to charge him enough to get him to just buy a new one. I carefully removed it from his home. I have 2 other mini splits that I installed myself and I love them....I have all necessary tools and know how to use them....what I don't know is if the outdoor unit will allow my nitrogen to flow all the way through it. How do I know if the entire system loop is accessible through the one service valve? Does the EEV need opened up with a doughnut magnet? Is there some refrigerant trapped in the compressor that could be contaminated with air/moisture.....how do I make sure I have a clean, dry, and tight system in this situation? I wish I could just make new flares, hook up the lines, open both hex ports add nitrogen to the one service valve on the larger line, fill it to 200 psig and crack the flare nut on the small line a let it purge out, then seal the system and do a leak test. Is it that easy? does the entire system loop pressurize ....or is there going to be some point where the nitrogen bypasses the compressor or EEV?

[@octavioussplevinski1409]

was the bro really brazing with normal, non tinted safety glasses....

[@sangeetachauhan1807]

Will be more helpful if speak slowly

[@mtz5582]

Somehow disappointed with the contents from the Chanel I dearly treasure.I am a rookie and the information delivered was too technical and only useful for advanced engineers.