Other than using a two-stage compressor, what is another method for capacity control?

The method of capacity control through using multiple compressors is a valid approach in HVAC systems. This strategy allows for increased flexibility and efficiency in managing cooling or heating load demands. When there are multiple compressors, they can operate independently or in tandem to match the system's output to the current thermal load required by the space being conditioned. For instance, during periods of lower demand, one compressor may be used to maintain efficiency while preventing unnecessary energy consumption. As demand increases, additional compressors can be activated to provide the required capacity.

Using a two-stage thermostat is not typically associated with capacity control, as it primarily serves to manage the operation of single or multiple-stage heating and cooling equipment rather than directly controlling capacity. A liquid line receiver is used for storing excess refrigerant during operation but does not serve as a method for adjusting capacity. Similarly, a stage outdoor fan is important for airflow but doesn't control capacity in the same manner as employing multiple compressors does. Thus, the virtue of using multiple compressors lies in its effectiveness in accommodating varying load requirements efficiently.