If the saturation temperature for 12 lb of pressure is 36.9°F and the actual refrigerant temperature is 35.2°F, what can be inferred about the refrigerant?

The scenario presented involves understanding the relationship between pressure, temperature, and the phases of refrigerants. The saturation temperature of 36.9°F indicates the temperature at which the refrigerant will change from liquid to vapor (boil) at a pressure of 12 lb. Since the actual refrigerant temperature is 35.2°F, which is lower than the saturation temperature, this indicates that the refrigerant is in a state where it is still in liquid form.

When the actual temperature is below the saturation temperature at the same pressure, the refrigerant has not yet reached its boiling point and therefore is not saturated with vapor. This means that the refrigerant is in the subcooled state, where it remains as liquid before it transitions to vapor.

Thus, understanding the differences in phases related to saturation temperature leads to the conclusion that the refrigerant is subcooled, as it is cooler than the temperature required to achieve saturation at that particular pressure.