What characteristic is used to define low-pressure appliances in terms of refrigerant pressure?

Low-pressure appliances are defined by their refrigerant pressure being below a specific threshold, which is 45 psia. This classification is important because it determines the handling, recovery, and recycling protocols for refrigerants used in these systems.

When refrigerants operate at pressures below 45 psia, they typically require different considerations in terms of design and safety, as well as compliance with regulatory standards. For instance, these appliances often use refrigerants with higher boiling points, making them suitable for specific applications where lower pressures are essential for operation.

Understanding this classification helps technicians recognize the appropriate techniques and equipment necessary for servicing low-pressure systems, ensuring compliance with safety regulations and effective system performance.