- (II) An ideal heat pump is used to maintain the inside temperature of a house at Tin = 22°C when the outside temperature is Tout Assume the heat pump does work at a rate of 1700 W. Also assume that the house loses heat via conduction through its walls and other surfaces at a rate given by (650 W/C°) (Tin - Tout). (a) For what outside temperature would the heat pump have to operate at all times in order to maintain the house at an inside temperature of 22°C? (b) If the outside temperature is less than you just calculated, what happens? (c) If the outside temperature is 8°C, what percentage of the time does the heat pump have to operate in order to maintain the house at an inside temperature of 22°C?

- (II) An ideal heat pump is used to maintain the inside temperature of a house at Tin = 22°C when the outside temperature is Tout Assume the heat pump does work at a rate of 1700 W. Also assume that the house loses heat via conduction through its walls and other surfaces at a rate given by (650 W/C°) (Tin - Tout). (a) For what outside temperature would the heat pump have to operate at all times in order to maintain the house at an inside temperature of 22°C? (b) If the outside temperature is less than you just calculated, what happens? (c) If the outside temperature is 8°C, what percentage of the time does the heat pump have to operate in order to maintain the house at an inside temperature of 22°C?

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter8: Natural Convection

Section: Chapter Questions

Problem 8.46P

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