Pressure controllers are categorized into two main classes based on what criterion?

Pressure controllers are primarily categorized based on their operational function in relation to the pressure of a system. The distinction between high and low pressure is critical in refrigeration and HVAC systems. High-pressure controllers are typically used to monitor and control the pressure in high-pressure zones of the system, ensuring that the components operate within safe limits, while low-pressure controllers manage the pressure in low-pressure zones. This classification is essential for maintaining system efficiency, safety, and operational integrity, as excessively high or low pressures can lead to malfunction, inefficiency, or even hazardous conditions.

The focus on pressure is paramount in refrigeration systems, where the pressure directly relates to the state and circulation of refrigerants. Hence, understanding this classification allows professionals to effectively manage the pressure control systems in refrigeration applications.