=+3-36. A building has a total heating load of 200,000 Btu/hr. The sensible heat factor for the space is 0.8 and the space is to be maintained at 72 F db and 30 percent relative humidity. Outdoor air at 40 F db and 20 percent relative humidity in the amount of 1000 cfm is required. Air is sup-

plied to the space at 120 F db. Water vapor with enthalpy of 1150 Btu/lbma is used to humid-

ify the air. Find

(a) the conditions and amount of air supplied to the space,

(b) the temperature rise of the air through the furnace,

(e) the amount of water vapor required, and

(d) the capac-

ity of the furnace. Assume sca-level pressure.