Refrigerant 410A Certification Practice Test

The low-pressure switch on an R-410A unit typically opens at around 50 psig. This pressure setting is designed to provide protection for the HVAC system by preventing it from operating when the refrigerant pressure falls below a certain level. Low refrigerant pressure can occur due to various issues, such as a refrigerant leak or inadequate system charge, which can lead to compressor damage if the system continues to run under these conditions.

Opening the switch at 50 psig allows the system to stop operating, encouraging technicians to investigate and resolve any underlying problems before the system is restarted. This proactive approach enhances the overall longevity and efficiency of the HVAC unit.

In contrast, the other pressure points listed do not represent the commonly established threshold for the low-pressure switch on R-410A systems, making them unsuitable in this context.