410A pump down

clammy

Knowing that 410 A is a blend, how critical is it when pumping down a system that you get the whole charge pumped down  .Or are you better off reclaiming it all instead of pumping down and then re charge with your re claim or put new in. I know when faced with a leak on a 410 system that you should reclaim ,repair ,pressure test and re charge w new refregerant due to the blend mix leaking at different rates but does this hold true on a pump down say to relocate units .Iuse to deal with blended refregernats many moons ago and don't remenber any issues butthis was well over 25 years ago i belive it was carrier carrine long time ago ,thanks for any inputpeace and good luck clammy

Techman

Pump Down

Assuming a leak in a system , you leak check and can't locate the leak , 2-3- times you leak check. What do you do? Recover and replace with new? I ALWAYS put new right in on top of the old.Its call "topping Off" and at one time it was NOT allowed , and now it is.  And I am not aware of any adverse side effects yet. My P/T readings sure seem awful close to normal,SubCooling/SuperHeat real close also. No complaints of uncomfort.  A regular pumpdown will claim all of the 410a ,regardless of the glide factor,which is real small anyway.Can your cond unit hold all the Freon in the system , you might need a reclaim drum to pumpdown the system.Liquid Line Filter/Driers  and Moisture/Indicators are used on 410a systems!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Spence

R-410A

This refrigerant, although a blend, does not fractionalize at conditions most of us will see, so those rumors of R-410A separating are false. Unless you're in Arizona with an ambient of 125, of course. More to worry about is that R-410A is a sponge, so more care is needed when brazing, evacuating, and choosing a drier.