The purpose of this white paper is to explain the energy code requirements for water‐cooled centrifugal chillers. I often get requests to send IPLV ratings for a centrifugal chiller to prove energy code compliance. However, unless the chiller is designed to operate at AHRI standard conditions (2.4 GPM/ton of chilled water leaving at 44°F and 3.0 GPM/ton of condenser water entering at 85°F), this is an invalid request. Figure 1 below from the 2015 WA State Energy Code establishes the rules for determining minimum efficiency levels for centrifugal chillers designed to operate at non‐AHRI Standard 550/590 conditions. Oregon uses ASHRAE 90.1-2016 which contains the same requirement. However, the baseline chiller efficiencies are slightly different in Oregon (see page 5).