Why is the oil in an R-123 chiller heated before it is removed?
Recovery techniques · EPA 608 Type III. The correct answer, and the reasoning behind it.
Liquid then vapor, heating oil, protecting water tubes, and high-pressure cut-outs.
The question
Why is the oil in an R-123 chiller heated before it is removed?
- Warm oil releases dissolved refrigerant, so less escapes with itCorrect answer
- Heating destroys acid so the oil can be reused
- Heating raises the shell pressure to the 5 psig limit for oil changes
- Heating boils water out of the oil for disposal
Why “Warm oil releases dissolved refrigerant, so less escapes with it” is correct
Refrigerant dissolves in chiller oil, and cold oil holds more of it. Heating the oil to about 130 °F drives the refrigerant out so it can be recovered rather than released when the oil is drained.
Source: EPA: Test Topics; EPA: Service Practice Requirements
Why the other answers are wrong
- Heating destroys acid so the oil can be reused — Heating oil does not neutralize acid.
- Heating raises the shell pressure to the 5 psig limit for oil changes — The 5 psig limit is a maximum, not a target the oil must reach.
- Heating boils water out of the oil for disposal — The purpose is to drive refrigerant out of the oil, not water.
Practice more of this
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