Refrigerant-Loop Certification

Manufacturers of products, certified by the Air-conditioning and Refrigeration Institute (ARI) Standard 870 - Direct Geoexchange Heat Pumps - for refrigerant-loop heat pump equipment, publish a capacity rating, cooling EER and heating COP for each model cataloged at the standard test fluid rating conditions of 77 F for cooling and 41 F for heating. ARI standards establish rating criteria and procedures for measuring and certifying product performance.

As it is not practical for the earth-to-refrigerant heat exchanger component of the system to be tested buried in the earth, an immersed heat exchanger test apparatus is used. The earth-to-refrigerant heat exchanger is placed in a tank containing a temperature-controlled fluid (water protected with the addition of a 15% by weight methanol) for test purposes. In this way, refrigerant-loop heat pump products are rated on a uniform basis so that buyers and users can properly make selections for specific applications.

You should not confuse the ARI Standard Efficiency Rating with the expression SEER. The latter stands for Seasonal Energy Efficiency Ratio. SEER is a measure of seasonal cooling efficiency under a range of weather conditions, assumed to be typical for a location, and of performance losses due to cycling under part load conditions.