Document 42wk5ywq26B1B5jgZrVDEK5V

American Society of Heating and Ventilating Engineers Guide, 1926-27 Thermostat Radiator trap elevation H Radiator trap--plan . c=n (=1 LZ3 S Expansion joint Column radiator--plan A Column radiator--elevation Wall radiator--plan D Wall radiator--elevation I Pipe coil--plan Pipe coil--elevation O Indirect radiator--plan 13 Indirect radiator--elevation K! 0 Supply duct---section Exhaust duct--section Butterfly damper^-plan (or elevation) Butterfly damper-elevation (or plan) Deflecting damper square pipe Vanes Air supply outlet Exhaust outlet IChapter HEAT LOSSES FROM BUILDINGS THE procedure to be followed in determining the heat loss from anybuilding can be divided into seven consecutive steps, as follows: 1. Determine on the inside air temperature, at the breathing line, which is to be maintained in the building during the coldest weather. 2. Determine on an outside air temperature for design purposes, based on the minimum temperatures recorded in the locality in question, which will provide for all but the most severe conditions. Such conditions as may exist for only a few con secutive hours are readily taken care of by the heat capacity of the building itself. 3. Select 'or compute the heat transmission coefficients for outside wall and glass, also for floor, or top-floor ceiling, if these are next to unheated space. Include roof if next to heated space. 4. Measure up net outside wall, glass and roof next to heated spaces, as welf as any- cold floor or ceiling next to unheated space. Such measurements are made from building plans. 5. Compute the heat transmission losses for each kind of wall, glass, floor, ceiling and roof in the building by multiplying the heat transmisison coefficient in each case by the area of the surface in square feet and the temperature difference between the inside and outside air. (See paragraphs 1 and 2 above.) 6. Select unit values and compute the heat equivalent of the infiltration of cold air taking place around outside doors and windows. These unit values depend on kind or width of crack and wind velocity, and when multiplied by the length of crack and the temperature difference between the inside and outside air, the result expresses the heat required to warm up the cold air leaking into the building per hour. 7. The Sum of the heat losses by transmission (paragraph 5) through the outside wall and glass, as well as through any cold floors, ceilings or roof, and the heat equivalent (paragraph 6) of the cold air entering by infiltration is the total heat required for warming any building. INSIDE TEMPERATURE The inside air temperature which must be maintained within a building, and which should always be stated in the heating specifications', is understood to be the temperature at the breathing line 5 ft. above the floor and not less than 3 ft. from the outside walls. Inside air tempera tures usually specified vary in accordance with the use to which the building is to be put, arid Table 1 presents values which are in conformity with good practice. Data prepared especially for The Guide by Arthur C. Willard, professor of Heating and Ventilation and Head of Department of Mechanical Engineering, University of Illinois, Urbana. 111. .5 >. /