In hot dry climates there are huge opportunities to improve air conditioner efficiency using evaporative technologies that reduce air temperatures at the condenser.

As outdoor air temperature increases, air conditioner efficiency falls quickly; and therefore, uses more energy to deliver the same amount of cooling to a space. This is compounded by the fact that during hotter periods the cooling needs for a space increases.


In the area of condenser air pre-cooling, our research attempts to answer the following questions:

  • How much energy can be saved in different climate zones by adding evaporative pre-cooling at the condenser?
  • How will water quality impact the air conditioning equipment, and are some technologies/designs inherently better at reducing the impact that water quality has on equipment?
  • What kind of water treatment and management strategies can be employed to extend the life of air conditioning equipment that has evaporative pre-cooling?


To answer the research questions above, WCEC is developing an evaporative pre-cooling test protocol to compare various market available residential condenser pre-cooling technologies. Air conditioner performance data is being collected with and without pre-cooling to look at the actual efficiency gains attributed to the technology. A visual inspection of the condenser coil will quickly inform whether water quality had an impact on the equipment, and other research on Water Management for Evaporative Systems will analyze the performance of different water treatment technologies that could reduce the impact that water quality has on these technologies.


For larger roof-top systems, WCEC is monitoring condenser pre-cooling technologies on a Target in Davis, CA. These include DualCool® and WicKool® which are retrofit technologies for RTUs. Pre and post monitoring will highlight the potential energy savings for these technologies in different climate zones. An overview of this specific research can be found at Retrofits for Rooftop Package Air Conditioners & Air Handlers.