Scent of refrigerant vs oil

JHZR2

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I'm trying to help diagnose the possibility of a slight evaporator leak. After sitting, the car in question (134a AC system) has a slight odor at startup. When running, there is nothing observable. It strikes me as the smell when a gauge set pops and some refrigerant and oil comes out. But it's not clear to me if odors of a 134a system are from the 134a itself, or if from the Poe/pag oil. I've obviously never huffed the stuff, and I don't vent it to the atmosphere. So does 134a smell or the oil?
 
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R-134a is completely odorless, all of the smell is from the oil and/or from the hoses and other rubber/polymer parts in the system outgassing a little bit into the refrigerant. Pure R-134a is also sold as "freeze-it" spray for diagnosing heat-related failures in electronic components. We use it a lot where I work, and it has no scent at all.
 
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Originally Posted By: 440Magnum
R-134a is also sold as "freeze-it" spray for diagnosing heat-related failures in electronic components.
R134a is also sold as 'canned air' for blowing crud out of keyboards and such.
 
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Originally Posted By: leeharvey418
Originally Posted By: 440Magnum
R-134a is also sold as "freeze-it" spray for diagnosing heat-related failures in electronic components.
R134a is also sold as 'canned air' for blowing crud out of keyboards and such.
since r134a is alledgly harmfull to the ozone they no longer use it.now they are using r152a in those cans
 

JHZR2

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Originally Posted By: 440Magnum
R-134a is completely odorless, all of the smell is from the oil and/or from the hoses and other rubber/polymer parts in the system outgassing a little bit into the refrigerant. Pure R-134a is also sold as "freeze-it" spray for diagnosing heat-related failures in electronic components. We use it a lot where I work, and it has no scent at all.
I have seen those sprays but they contain bitterant (the ones Ive encountered) which skews the basis for the hydrocarbon scent.
Originally Posted By: Quest
to properly diagnose refrigerant leak is to add UV dye into the system and then shine it with UV light. Q.
I understand that. The only info I have to go off of now is scent, and Ill try to help diagnose this situation with more appropriate techniques as it makes sense (first Ill use a sniffer).
 
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the only part of the ac system thats in the car is the evaporator.if you smell pag oil thats all it can be. may want to sniff a bottle of pag to compare the smells.i have plenty if your up for a road trip smile
 
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Originally Posted By: Chris142
since r134a is alledgly harmfull to the ozone they no longer use it.now they are using r152a in those cans
Um... R134a is 1,1,1,2 tetrafluoroethane, with nary a chlorine atom to be found in its structure. It's the ozone-friendly replacement for R12 (dichlorodifluoromethane).
 
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Originally Posted By: leeharvey418
Originally Posted By: Chris142
since r134a is alledgly harmfull to the ozone they no longer use it.now they are using r152a in those cans
Um... R134a is 1,1,1,2 tetrafluoroethane, with nary a chlorine atom to be found in its structure. It's the ozone-friendly replacement for R12 (dichlorodifluoromethane).
if it was ozone safe and why do we have to capture and recycle every ounce of it in an AC system? now they are telling us that it is not o zone safe and it is being replaced by another refrigerant
 
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Originally Posted By: leeharvey418
Originally Posted By: Chris142
since r134a is alledgly harmfull to the ozone they no longer use it.now they are using r152a in those cans
Um... R134a is 1,1,1,2 tetrafluoroethane, with nary a chlorine atom to be found in its structure. It's the ozone-friendly replacement for R12 (dichlorodifluoromethane).
It's not a problem with Ozone depletion. R134a has a Global Warming Potential of 1300. Co2 is a 1, the baseline.
 
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