Refrogerant is a pressurized gas so you don't "drain" it. You need an A/C recovery machine to reclaim the refrigerant and recharge it with the proper amount. I don't know why you are doing this but it's not a fluid that needs changing. You would only do this to know exactly how much refrigerant is in the system.
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Monday, August 8th, 2011 AT 10:04 AM