If an evaporator is rated at 120,000 BTU/HR, what size must the condenser be?

The correct choice is that the condenser must be larger than the rated evaporator. This is because an evaporator and a condenser work together in a refrigeration cycle, and their sizes need to be appropriately matched to ensure efficient operation.

In a properly functioning system, the condenser must be capable of handling and dissipating the heat absorbed by the evaporator. When the evaporator absorbs 120,000 BTU/hr of heat, it is necessary for the condenser to be able to reject at least that amount of heat to maintain the balance of the cooling cycle. If the condenser were the same size or smaller than the evaporator, it might become overloaded and unable to effectively dissipate the heat, leading to inefficiencies and potential system failure.

Condenser size is crucial for adequate heat exchange, allowing the refrigerant to convert back from gas to liquid effectively while maintaining required pressures in the system. Therefore, opting for a condenser larger than the rated evaporator helps to ensure reliability and efficiency in energy use and overall system performance.