How to Improve Vehicle R134a A/C System Performance with a Liquid Line Suction Line Heat Exchanger (IHX)

Over the past decades, automotive air-conditioning systems have been undergoing constant improvements to achieve higher efficiency and also for addressing environmental concerns. Long used in home refrigerators, a liquid-line-suction-line heat exchanger (LLSLHX), also termed internal heat exchanger (IHX), has not been given much attention for use in automotive A/C applications. In this work, we applied the IHX as a drop-in component (without changing other components in an existing system) to a production vehicle in order to improve the performance of R134a A/C systems (both CCOT and TXV). We also discussed issues relating to vehicle A/C system performance enhancement with the application of an IHX.