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Question 7.E.51: A heat pump with a COP of 1.4 is to produce a 100,000 Btu/h ......

A heat pump with a COP of 1.4 is to produce a 100,000 \mathrm{Btu} / \mathrm{h} heating effect. How much power does this device require, in hp?

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The COP and the heating effect of a heat pump are given. The power input to the heat pump is to be determined.

Assumptions The heat pump operates steadily.

Analysis Applying the definition of the coefficient of performance,

\dot{W}_{\text {net,in }}=\frac{\dot{Q}_{H}}{\mathrm{COP}_{\mathrm{HP}}}=\frac{100,000 \mathrm{Btu} / \mathrm{h}}{1.4}\left(\frac{1 \mathrm{hp}}{2544.5 \mathrm{Btu} / \mathrm{h}}\right)=\mathrm{2 8 . 1 \mathrm { h p }}

7.51

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