EPA Type 2 Practice Test

Phase and density matter for how fast you can remove refrigerant. Liquid refrigerant is much denser than vapor, so a recovery device moves more mass per unit time when it’s pulling liquid. That means you can drain the system faster until the liquid charge is gone, compared with recovering only vapor, which has far lower density and requires the machine to handle gas and often condense or compress it first. Solid isn’t a typical state for refrigerants in normal recovery scenarios, so it wouldn’t be the phase associated with the shortest recovery time. Therefore, liquid refrigerant yields the shortest recovery time.