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Old 05-25-2016, 07:18 AM
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vstech vstech is offline
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Join Date: Mar 2006
Location: Mount Holly, NC
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Quote:
Originally Posted by leathermang View Post
That is just not true. The oil accumulates in the lower pockets of the system and pulling with recovery machine does not have the ability to move that oil out....
The MB FSM says to take the system apart... not that many parts... and flush each one... cap, put back together, do the dry pressure test, etc...
Jay Bob had a good post...
Check out the AC thread in my signature...
I don't know... But refrigerant does dissolve and carry oil. It's the reason we can't use mineral oil with 134, we have to use an oil that will dissolve in the refrigerant.
So, while simply blowing refrigerant through the system would leave puddles of oil in low spots, a recovery machine should be able to move liquid refrigerant through the system and take with it, most if not all the oil after a few passes. I've never heard of this practice, but it does make sense.
I know my recovery machine has an oil separator, designed for measuring the exact amount of oil removed during a recovery operation, so the exact amount can be returned. I do not know if repeated recoveries would remove all the oil, or clean out a system.
But I do understand how it would.
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