What happens to the refrigerant inside the evaporator of an R-410A system?
Refrigeration · EPA 608 Type II. The correct answer, and the reasoning behind it.
Identifying refrigerants, system components and the state of refrigerant in each.
The question
What happens to the refrigerant inside the evaporator of an R-410A system?
- Low-pressure liquid boils into vapor as it absorbs heatCorrect answer
- High-pressure vapor condenses into liquid
- Vapor is compressed to a higher pressure
- Liquid is subcooled before it reaches the metering device
Why “Low-pressure liquid boils into vapor as it absorbs heat” is correct
In the evaporator, low-pressure refrigerant boils from liquid into vapor as it absorbs heat from the air or water being cooled. That is where the cooling happens.
Source: EPA: Test Topics
Why the other answers are wrong
- High-pressure vapor condenses into liquid — Condensing happens in the condenser.
- Vapor is compressed to a higher pressure — Compression happens in the compressor.
- Liquid is subcooled before it reaches the metering device — Subcooling happens at the end of the condenser.
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