Why should a container of polyolester (POE) oil be kept tightly sealed until it is used?
Substitute refrigerants and oils · EPA 608 Core. The correct answer, and the reasoning behind it.
Why there are no true drop-in replacements, and fractionation in blends.
The question
Why should a container of polyolester (POE) oil be kept tightly sealed until it is used?
- The oil evaporates quickly at room temperature
- The oil turns into a flammable gas when opened
- The oil readily absorbs moisture from the airCorrect answer
- The oil loses its color and can no longer be identified
Why “The oil readily absorbs moisture from the air” is correct
POE oil is hygroscopic: it pulls moisture out of the air. Moisture in the system can form acids and sludge, so POE should be kept sealed and added from a fresh, closed container.
Source: EPA: Test Topics
Why the other answers are wrong
- The oil evaporates quickly at room temperature — POE oil does not evaporate readily.
- The oil turns into a flammable gas when opened — Opening the container does not turn the oil into a gas.
- The oil loses its color and can no longer be identified — Color change is not the reason for keeping it sealed.
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