R-1234yf absorbs slightly less energy per unit of flow in a refrigerant cycle compared to R-134a. In order to compensate for that differential, yf systems utilize an Internal Heat Exchanger (IHX). The IHX (sometimes called a Suction Line Heat Exchanger
Expansion Valves: The expansion valve is a complex valve which regulates refrigerant flow at the evaporator inlet with an internal moving rod mechanism. This rod opens and closes to differing heights based upon the cooling burden put upon the system.