ICC Commercial Mechanical Practice Exam

R-401B Refrigerant is a blend of which components?

1. R-22/152a/124 (33/15/52)

2. R-22/152a/124 (61/11/28)

3. Pentafluoroethane

4. Propane

The correct answer is: R-22/152a/124 (61/11/28)

R-401B is a refrigerant blend that specifically consists of three components: R-22, R-152a, and R-124. The proportions of these components in R-401B are 61% R-22, 11% R-152a, and 28% R-124. This blend is significant because it was developed as a replacement for R-12 in refrigeration applications while maintaining similar performance characteristics. The inclusion of R-22 provides good cooling capacity and efficiency, while R-152a and R-124 enhance the properties of the blend, making it suitable for specific temperature ranges and pressures found in refrigeration systems. In contrast, the other options do not accurately reflect the composition of R-401B. While option A presents a different ratio, it represents another blend or mixture but does not correspond to the R-401B formulation. The components listed in option C, Pentafluoroethane, is an individual refrigerant and does not reflect the blend of R-401B. Similarly, option D, propane, is a different refrigerant type altogether and not a component of R-401B. Understanding the specific blend and its composition is crucial for applying the correct refrigerant in systems designed