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A. 1) In favorable climates and buildings types, natural ventilation can be used as an alternative to air-conditioning plants. 2) At interior air velocities of 160 fpm, the perceived interior temperature can be reduced by as much as 5°F. 3) Wind can blow air through openings in the wall on the windward side of the building, and suck air out of openings on the leeward side and the roof. 4) Temperature differences between warm air inside and cool air outside can cause the air in the room to rise and exit at the ceiling or ridge. 5) Power ventilation can be accomplished in two ways. 6) In homes not mechanically cooled (air conditioned) the temperature can be controlled to some extent by the use of attic fans. 7) Sufficient outlets must be installed in the attic to exhaust the air without creating high pressures against which the fan must operate. 8) The net area of attic outlets should be 1/800th of the rated fan volume in cfm and 1/8 inch static pressure. 9) The outlets should be distributed uniformly. 10) Air conditioned homes can use power attic ventilators by installing an exhaust fan through the roof or in the gable. 11) Inlets for the ventilating air should be at the soffit, or the opposite gable, when no roof overhang exists. 12) For well-insulated ceilings it is doubtful that power ventilation can be justified economically. 13) There are some attics which cannot be ventilated by gravity or wind-assisted methods. 14) Consideration should be given to the use of a power ventilator with automatic or motorized inlet louvers. 15) Ventilation can be shut off during a dust storm to prevent the buildup of dust and sand in the attic.
B. 1) A tremendous amount of work had to be done to make present scientific achievements possible. 2) The explanation of combustion is to be found in the chemical combination of the burning substance with the oxygen of the air. 3) If good results are to be obtained, care should be taken in all cases to insulate well the space between the coils and the floor above. 4) Automatic starting and stopping of the fan should be done by a wall-type thermostat. 5) This control valve will not have to mix warm and cold water. 6) A thermostat can be influenced by outside air and gravity cooling effect of the unit. 7) Since the air in the system was untreated it had to be introduced directly into the fan-coil unit.
ACTIVE VOCABULARY
Give Russian equivalents of the following words and phrases. Try to memorize them.
Nouns and noun phrases
| depressurization | ||
| cavity | ||
| crawlspace | ||
| fume | ||
| pollen | ||
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