Can You Trust Your Micron Gauge? 

You figured right

Using a micron guage doesnt prove there isnt a leak. First its my understanding it doesnt even measure vacuum but rather temperature. Second a vacuum pump will overcome any leak in the system that isnt substantial and a 5min leak test isnt realistic. I even called the techs at one of the major companies and he even said " to have an actual micron guage would be in the thousands, its promoted to ensure people keep their pumps on longer." Last point. A perfect vacuum is only -14.7psi. Good luck if you think that is a suitable pressure test.

@@gabooda2380 nice RU-vid science there bud. “I called” and “I talked to” doesn’t mean shit. It means you got another persons “opinion”. I’ve had units hold 350psi for 24 hours without a kick of drop.. then leak under vacuum. Pressure test it.. vacuum it deep… and make sure it holds a decay. If there is a leak that passed that stuff.. then it is what it is. People who work in the real world know that half this “by the book” shit doesn’t translate to something that is reasonable in the real world service calls. I work on a lot of junk. And I flat would be out of a job if I spent the time chasing the half the crap I learned was “right”. I dare you to take a 25 year old cooler, make a repair, and try to even get that thing to pull down to “proper vacuum” and hold a “decay test” You’ll spend the entire day pulling your hair out as the oil in the compressor releases refer under vacuum causing you to fail the 5 minute decay test you say “isn’t good enough”. System is tight, refer boils out of oil. Madness in-sues while you try to find a leak that doesn’t exist. But based of your comment you don’t do anything but new installs. So keep living in your fantasy land till you go do service. Hopefully you end up working with a guy who’s been doing it for awhile and slaps some sense into you.

@@nsboost My "fantasy world" you speak of started in '92. I have been in the field pretty much EVERY day since. I work on both new and wet systems. So, I dont need anyone to "slap some sense into me" Also, my "youtube science" facts you talk about came from an engineer/tech at one of the major test instrument manufacturers. Its a shame hes such an idiot by your standards. But you could always do your own research regarding vacuum transducers, thermistors, and even pirani sensors. Hell, the fact that many micron guages are constantly recalibrating should be a clue. The micron guage doesnt measure vacuum pressure directly. It measures temperature or thermal conductivity/heat loss of the air around the sensor. It measures the cleanliness of the system. Refrigerant doesnt need vacuum to boil off. Moisture does bc we dont live in a 212°F ambient condition. With the POE oil you cant even get the moisture out of the oil without a filter dryer. So thats pointless. So as I said holding 500microns for 5mins doesnt prove you dont have a leak. Its possible you have a very small leak in relation to the total system capacity in a clean and dry environment. They "sell it" as the be all, end all "look ma no hands" and its not. Its just another tool whos reading needs to be interpreted based on the situation. On a wet system maybe a person should blank off his guage mid evacuation and clean it the same as changing his pump oil?

I will remember that tip.

Good to know... Might come in handy. They've been crazy recently.

That’s what they all have in common.

Which one you recommend to rock with?

@@techti8792 the new Fieldpiece looks good wireless and has a screen

I’m gonna follow this video up with some stuff that might address a few of those things as well.

@@HVACShopTalk do one with an old compressor filled with old used oil attached to your line set. Bring down the vacuum and hold and let it decay and steady out. Then strike the bottom of the compressor with a small 2 pound mallet and watch what happens.

Me too man. I like doing these tests so I can get to the bottom of this stuff.

Thank you sir

Trane

These gauges are the ones that I personally own

Starting to try out their power tools as well.

I tested my personal gauges so there is a mix.

I’d say you’re wrong about that then

Outstanding Comedy

Outstanding test. Good show old boy, Good show.

I was going to follow this video up with a video where I show the difference between micron readings during the vacuum when the gauges are in different parts of the system.

I get it