Design a heating system for a small factory in Denver, Colorado. This is a multistep problem that is continued in subsequent chapters. In the first step, you are to determine the heating load on the building, i.e., the rate at which the building loses heat in the winter, if the inside temperature is to be maintained at 20°C. In order to compensate for this heat loss, you subsequently are asked to design a suitable heater that provides a rate of heat transfer equal to the heat load from the building. A schematic diagram of the building and construction details for the walls and ceilings are shown in the figure on the next page. Additional information may be obtained from the ASHRAE Handbook of Fundamentals. For the purpose of this analysis, it is assumed that the ambient temperature in Denver is equal to or greater than 210°C 97% of the time. Furthermore, air infiltration through windows and doors is assumed to be approximately 0.2 times the volume of the building per hour. For the initial estimate of the heat load, use average values for the convective heat transfer coefficients over the inside and outside surfaces from Table 1.4. Note that for this design, the outside temperature assumes the worst possible conditions and, if the heater is able to maintain the temperature under these conditions, it is able to meet less-severe conditions as well.
After you have completed the initial design, examine the results and prepare a report for the architect and the owner of the building, pointing out how the thermal design could be improved. Note especially any areas where excessive heat losses may occur. After one has studied Chapters 5 and 8, the heat loss calculations can be repeated by using the heat transfer coefficient from information presented in those chapters.

Data from in Table 1.4

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3.0 m 10 m Sloping roof Windows (4) 25 m 2.5 m 0.75 m Wall Cross Section