In: Mechanical Engineering
A heat pump-bases HVAC system can remove heat from a building by
(a) compressing the refrigerant to make it hotter than the outside air
(b) compressing the refrigerant to make it cooler than the outside air
(c) expanding the refrigerant to make it hotter than the outside air
(d) blowing the heat out of the building using a fan
The correct answer is the option (A).
EXPLANATION
HVAC System based Heat Pump consists of a Vapour Compression Refrigeration cycle, and hence last two options (c) & (d) gets eliminated.
Now for removing heat from a building, that is, for cooling purpose refrigerant need to take heat from inside air and exchange it with outside air so that heat from inside air is extracted and gets transferred to outside air.
Now to transfer heat through the heat exchanger to outside air, the temperature of refrigerant need to me more than the temperature of outside air and hence option (A) is the correct answer.
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