EPA Section 608 Universal Certification ExamCoreMedium
A technician is installing a new split system using R-410A. Which type of oil is recommended for use with R-410A?
- AMineral oil (MO)
- BAlkylbenzene (AB)
- CPolyolester (POE) oil
- DPolyalkylene Glycol (PAG)
Show answer & explanationAnswer & explanation
Correct answer: C. Polyolester (POE) oil
R-410A is an HFC refrigerant and is incompatible with traditional mineral oil or alkylbenzene oils. It requires the use of Polyolester (POE) oil, which is miscible with HFCs.
Why the other options are wrong
- A. Mineral oil is used with CFCs (e.g., R-12) and HCFCs (e.g., R-22), not HFCs like R-410A.
- B. Alkylbenzene oil is used with some HCFCs and CFCs, but not HFCs.
- D. Polyalkylene Glycol (PAG) oil is primarily used in automotive air conditioning systems with HFC-134a, not typically residential or commercial R-410A systems.
HFC Refrigerant Oils
HFC refrigerants like R-410A require synthetic Polyolester (POE) oils for proper lubrication due to their immiscibility with traditional mineral or alkylbenzene oils.
- POE oil is hygroscopic (absorbs moisture readily).
- Proper handling is crucial to prevent moisture contamination.
- Different refrigerants require specific oil types for optimal performance and system longevity.
- Mixing incompatible oils can lead to compressor failure.
Memory trick: HFCs need POE, for their proper way.