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Question 14.7: A vapor compression heat pump delivering 28 kJ/s of useful h......

A vapor compression heat pump delivering 28 kJ/s of useful heat for heating purposes operates with a COP of 4.
Calculate the compressor input power and the rate of heat addition in the evaporator.

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1. Compressor input power

P_{\mathrm{cr}}=Q_{\mathrm{h}}/\mathrm{COP}=28/4=7\,\mathrm{kW}

2. Rate of heat addition in the evaporator

Q_{\mathrm{ev}}=Q_{\mathrm{h}}-P_{\mathrm{cr}}=28-7=21\,\mathrm{kW}.

Seasonal COP of a heat pump is calculated in Example 14.8.

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