A heating system must maintain the interior of a building at 25C during a period when...

  

Transcribed Image Text:

A heating system must maintain the interior of a building at 25°C during a period when the outside air temperature is 5°C and the heat transfer from the building through its roof and walls is 6 x 106 kJ. For this duty heat pumps are under consideration that would operate between the dwelling and: (a) the ground at 15°C. (b) a pond at 10°C. (c) the outside air at 5°C. For each case, evaluate the minimum theoretical net work input required by any such heat pump, in kJ. A heating system must maintain the interior of a building at 25°C during a period when the outside air temperature is 5°C and the heat transfer from the building through its roof and walls is 6 x 106 kJ. For this duty heat pumps are under consideration that would operate between the dwelling and: (a) the ground at 15°C. (b) a pond at 10°C. (c) the outside air at 5°C. For each case, evaluate the minimum theoretical net work input required by any such heat pump, in kJ.