HVAC - EPA Certification Practice Exam

Nitrogen is commonly used in an HVAC system for various purposes, and one of its key applications is to increase pressure in water-logged systems. When a system experiences water logging, it can lead to inefficiencies and potential damage. By introducing nitrogen into the system, technicians can effectively raise the pressure, which helps to push out any trapped moisture and allow for proper functioning.

Using nitrogen this way is advantageous because it helps to avoid introducing moisture that can occur if using air, which contains water vapor. Nitrogen is dry and inert, making it an ideal choice for maintaining the integrity of the HVAC system while addressing water logging issues.

In contrast, while nitrogen can also be used in other scenarios, such as charging refrigerant and testing for leaks, those uses have specific protocols and considerations. Purging the system can involve using nitrogen as well, but its primary role in maintaining system efficiency during water logging is crucial.