Assume the house in Problem 9.129 has a combined 12 000 kg hardwood, 2500 kg gypsum plates (C_p = 1 kJ/kg-K), and 750 kg steel, all of which is at 20◦C. If the heat pump is turned off, how fast does the house cool down (◦C/s)?

Data from Problem 9.129

A new air conditioner using R-410a is used in heat pump mode. The high pressure is 2000 kPa and the low pressure is 400 kPa. It warms a house at 20◦C driven by an electric power input of 2 kW in an ambient at −5◦C. Find the destruction of exergy in four places: 

(1) Inside the heat pump, 

(2) In the high-T heat exchanger, 

(3) In the low-T heat exchanger, and 

(4) In the house walls/windows, and so on that separate the inside from the outside of the house.