Hey guys just want to make sure im doing my evacuations correctly.When i vacuum out a system i remove the schrader cores and use vacuum rated hoses 3/8's. When i get down to 500 microns i stop the pump and watch for micron rise. Once i determine i dont have any leaks i open up my service valves in the condenser and release the refrigerant. Is that the way you guys vac out your systems? I just make sure i dont remove my hoses off the system while is under a vacuum so i wont let any air in the system.
Evacuation process?
Junior1983
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Which type of metering device allows "a NOT full LL at the metering device", so, I think they all want /require a full LL feeding their metering device. So, if the LL is full under all "normal" operating , then I think by me "seeing" that the LL is full should not change a thing. Charging a system in cool/cold by the SG CAN/WILL lead to problems in warm weather , but that is because the "freon charger" didn't know what he was doing.Not the fault of the SG. I find the MI part an extremely valuable "tool". I sell very,very few comp/CU's. Only 3-4 this year, so far! I sell lots of LL/SL/FD's.
I didn't say it was the sight glass' fault I just said it causes "techs" to improperly charge systems. Moisture indicator is nice but IMO it's just an unnecessary additional cost on a resi split, I've seen lots of glasses leak too. If you can measure SC then you have a full LL, I don't need a glass to see it.
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OK, OK, how about you look at "good" MI part and don't look at that no good ,dirty rotten skunk part of the SG. I tried and I just can't.
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Maybe they were my customers at some time. To me, a new customer usually means SGMI, FD's, CCH, etc,etc. And more FD's.I guess you have good Tech's in your area ,so, no moisture ,so, no SGMI. OK.I get it.
You open all your new customers systems just to add a SG and filter driers? That would mean each customer automatically gets a ~4 figure bill right off the bat for no gain to them.
I bet the guys behind the parts counter know you as the guy who buys all them sight glasses, more than any other tech in town. 
I can see your point about moisture, but correct evacuation procedures and standing blank off tests will demonstrate the absence of moisture. If you have water in the system, you won't be able to pull under about 2000 microns because it will be boiling off and making everything cold. If you can get a system to (say) 150 microns and it doesn't rise above 300 or so in the next several minutes, you've essentially proven that there is no further moisture to boil off and the dryer catches any other contaminants. The only way for moisture to get back in is if the system is opened again.
I can see your point about moisture, but correct evacuation procedures and standing blank off tests will demonstrate the absence of moisture. If you have water in the system, you won't be able to pull under about 2000 microns because it will be boiling off and making everything cold. If you can get a system to (say) 150 microns and it doesn't rise above 300 or so in the next several minutes, you've essentially proven that there is no further moisture to boil off and the dryer catches any other contaminants. The only way for moisture to get back in is if the system is opened again.
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The guys behind the counter know me as the guy who doesn't buy comp/CU from them, or from ANY supply houses. Just 3-4 so far this year. I do 99% service so I get new customers w/ problems, my existing customers have very few problems. I replace more parts during a routine than I do during the rest of the year. What? You don't want a routine? I don't want you as a customer!
MI's mean 1 thing.
Moisture,and a LOT of it.Period.
Your MI is "wrong",you have a BIG problem.(likely contaminated)
It's NOT going to get down to the "nitty gritty" bro.Sorry.Just how it is.They are an Indicator of a potentially fatal Issue,not some kind of "micron gauge" Savior.
Good evening Gentleman.
Have a Great Day Tomorrow.It's gonna be HOT and an upstairs equip room with no ventilation awaits.:cheers:
Moisture,and a LOT of it.Period.
Your MI is "wrong",you have a BIG problem.(likely contaminated)
It's NOT going to get down to the "nitty gritty" bro.Sorry.Just how it is.They are an Indicator of a potentially fatal Issue,not some kind of "micron gauge" Savior.
Good evening Gentleman.
Have a Great Day Tomorrow.It's gonna be HOT and an upstairs equip room with no ventilation awaits.:cheers:
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jtrammel, YES I DO, open every system and add a SGMI/FD. The benefit is a clean dry system that protects the comp. I "get" these new units/customers because of the "other" HVACR guy didn't satisfy the customer, AND I DON"T TRUST THE OTHER HVACR GUY/GUYS. And we are not talking 4 digit #$#$. Now, washing a CU/Evap, FD, SGMI,CCH, Contactor,Pot relay/cap, Freon, 4-5 hrs labor and then I am talking 4 digits. I agree that if the INITIAL install is done correctly there is no need for a SGMI, but I get systems that have been "looked at"by others ,so, all bets are off. I did hundreds, and hundreds of "piping and startup" for a Tinknocker Contractor and I installed SGMI/FD on EVERYONE of those systems.
So i had an opportunity today to use a micron guage. my pump wouldnt hardly get below 640 or so in a reasonable time on a multi head mini. Gonna change the oil and pull the core out tomorrow on an evap coil swap.
Looking at the appion micron gauge in the near future if its not too much it comes with a FREE CRT
Looking at the appion micron gauge in the near future if its not too much it comes with a FREE CRT
Good for you! Ive seen a sight glass on a split system, that was the lennox dist.
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And good for you!So i had an opportunity today to use a micron guage. my pump wouldnt hardly get below 640 or so in a reasonable time on a multi head mini. Gonna change the oil and pull the core out tomorrow on an evap coil swap.
Looking at the appion micron gauge in the near future if its not too much it comes with a FREE CRT
It's my understanding that while 500 is the magic number - what's even more important is what happens when you stop the pump and isolate the system for the hold test. It will creep; but as long as it doesn't rise above a grand or so you are good. If I recall correctly, all the Carrier manuals considered holding at 1200 and under a "tight, dry system."
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Core_d, are you trying to say that "eventually" IS HERE?? Good Man!!!!
Wait til you have a sensitive/accurate micron gauge, you'll end up scrapping everything you use now and using 2 vcrts and large diameter hoses straight to the pump. A good micron gauge will quickly show you how crappy you've been doing evacuations. Ask me how I know... I dropped almost a grand on a new set up when I got my bluvac, but now I can pull most any system below 500 in 20 minutes or less. A new install with fresh line set and coil I can get it to 200-300 in a few minutes.So i had an opportunity today to use a micron guage. my pump wouldnt hardly get below 640 or so in a reasonable time on a multi head mini. Gonna change the oil and pull the core out tomorrow on an evap coil swap.
Looking at the appion micron gauge in the near future if its not too much it comes with a FREE CRT
Agree jt.
Pulling the valve cores is about the most important step as They offer the MOST restriction and some of the Newer hoses valve core depressors just plain stink as,I guess due to low loss crap,don't depress the schraider as much as the old guy's did.I've notice lately as just even getting a pressure reading was "marginal" on Them.WHich tell's me they are not functioning a "expected".
Pulling the valve cores is about the most important step as They offer the MOST restriction and some of the Newer hoses valve core depressors just plain stink as,I guess due to low loss crap,don't depress the schraider as much as the old guy's did.I've notice lately as just even getting a pressure reading was "marginal" on Them.WHich tell's me they are not functioning a "expected".
Havent bought one myself yet but this thread has definitely moved it up on my list. Used one of my coworkers sman 3s today with the micron gauge pulled an evap coil and linset down to about 430 microns didnt try it with the crt as had plenty else to do at that point.
I've never used the micron giage function on the Smans but I don't see how the unit that measures 500psig of refrigerant pressure and has refrigerant and system oil in it all the time could be anywhere near accurate yo read microns of mercury.
Fixed Orifices on a/c and heatpumps
True, but it is a great verification that your meters are accurate or that the refrigerant is pure.
Appion is an excellent choice for a micron gauge. Blu-Vac also.So i had an opportunity today to use a micron guage. my pump wouldnt hardly get below 640 or so in a reasonable time on a multi head mini. Gonna change the oil and pull the core out tomorrow on an evap coil swap.
Looking at the appion micron gauge in the near future if its not too much it comes with a FREE CRT
To the nay-sayers: There are certain tools that a knowledgeable tech would not be without. Would anyone take their sore foot to a doctor that didn't have an x-ray machine?
The only good thing about not having an accurate micron gauge is that "Ignorance is Bliss".... and boy do I miss that
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penderway, KindaSorta, on a 50' LL, going up 30' ,5' horizontal outside, and 15' H in the attic, where does the "not full LL begin" ? Not a joke, I don't know.
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