Question

32. An air-conditioning system is used to maintain a house at 65oF when the temperature outside is 85oF. The house is gaining heat through the walls and windows at a rate of 1250 Btu/min, and the heat generation rate within the house from people, lights, and appliances amounts to 350 Btu/min. Determine the minimum power input required for this air-conditioning system. A

Answer 1

Solution;

$T_L=65°F$

$T_H=85°F$

$Q=1250+350=1600Btu/min$

min

$COP=\frac{1}{(\frac{T_H}{T_L})-1}$

$COP=\frac{1}{(\frac{85+460}{65+460})-1}=26.25$

$P_{in}=\frac{Q}{COP}=\frac{1600}{26.25}=60.95Btu/min$