A space requires cooling in the amount of 120,000 Btufhr (35.2 kW) with a SHF of 0.5. Room conditions are 75 F (24 C); 50 percent relative humidity (RH). Outdoor air conditions are 90 F db and 75 F wb (32 C db and 24 C wb, respectively). One-third of the supply air is outdoor air. The coil SHF is 0.6 and can cool the air to 90 percent relative humidity (RH). Devise a system of processes to condition the room using Chart 1a, and compute heat transfer and flow rates for all the processes. Assume local elevation of 5000 ft (1500 m).
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