By removing energy by heat transfer from a room, a window

Chapter 5, Problem 5.62

(choose chapter or problem)

By removing energy by heat transfer from a room, a window air conditioner maintains the room at \(22^{\circ} \mathrm{C}\) on a day when the outside temperature is \(32^{\circ} \mathrm{C}\).

(a) Determine, in kW per kW of cooling, the minimum theoretical power required by the air conditioner.

(b) To achieve required rates of heat transfer with practical-sized units, air conditioners typically receive energy by heat transfer at a temperature below that of the room being cooled and discharge energy by heat transfer at a temperature above that of the surroundings. Consider the effect of this by determining the minimum theoretical power, in kW per kW of cooling, required when \(T_{\mathrm{C}}=18^{\circ} \mathrm{C}\) and \(T_{\mathrm{H}}=36^{\circ} \mathrm{C}\), and compare with the value found in part (a).