Heating and cooling buildings accounts for 40% of total energy consumption in the U.S. This tutorial on refrigeration cycles steps through calculations needed to predict temperatures, pressures, and flowrates in a refrigeration loop.

Note: the video recording cut out about 1 minute before the end. The answers are:

1. From the evaporator, find the mass flow: 833 lbm/hr
2. From the compressor, find the work required: Ws = -15,000 BTU/hr
3. From the condenser, find the cooling rate: -75,000 BTU/hr
4. Check the overall balance: 0 = Qcond - Ws + Qevap = 60,000 - (-15,000) + (-75,000) = 0