Residential HVAC Installation Practice Exam

Noncondensable gases refer to any gas that cannot be cooled and condensed into a liquid form within the refrigeration system. These gases are considered undesirable as they can cause issues with the functionality and efficiency of the system. Option A, while important for proper operation, does not accurately describe noncondensable gases. Option C is incorrect as noncondensable gases are not used as a coolant in a refrigeration system. Option D is also incorrect as noncondensable gases are not recommended for use in HVAC systems.