John is concerned that the compressor appears to be much too hot to touch, a sign perhaps that the compressor requires maintenance. John knows that the compressor consumes 26 Btu/lbm of throughput and that less than 2% of the electricity that the compressor draws must be lost to heat. Here are the data that John also has at hand:
Working Fluid = Freon 134a, Pi = 60 psia, Pe = 160 psia, Ti =70oF, Te =160oF Volumetric flow rate in = 140 ft^3 /min
1. What is the rate of heat loss in Btu/min?
2. What is the change in enthalpy of the working fluid as it passes during the compressor in Btu/lbm.
3. Please perform a First Law Reduction with the compressor as the system.
4. At $0.10/kW-hr what is the total cost of heat loss in $/year?
5. What is the rate of heat loss as a percentage of the electrical energy draw?
6. Must John recommend maintenance on the compressor? Please defend your answer