A building or space within a building may be used in many different ways. For each of these applications, the HVAC designer must determine the general criteria from personal experience or study and then add the special requirements of the user of the particular facility. 

The ASHRAE handbooks contain chapters on many common and exotic applications. The discussions which follow are limited to some of the more common applications. 

In every environment there are concerns for temperature, relative humidity, sound level and character, and the general quality of breathable air. In general, the higher the standard to be met, the more expensive the system will be to install, and probably to operate.

Two essential residential criteria are adequate comfort and the need of occupants to be able to adjust the controller set point. In larger residences (over 2400 ft2), the use of multiple HVAC systems should be considered, to allow zoning. 

These criteria extend to apartments and hotel or motel guest rooms. First cost and operating cost are concerns, as are simplicity and an acceptable sound level [from 30 to 40 noise criteria (NC)].

Commercial offices
Two basic needs are comfort and an adequate ventilation rate (airflow in cubic feet per minute per square foot or per person)—so that occupants will not complain of stuffy or dead air. 

Where smoking is allowed, the ventilation rate and the amount of outside air must be increased. 

Controls are often designed to be nonadjustable by occupants. Zoning must be provided to compensate for use, occupant density, and exterior exposure. 

Conference rooms and corner offices should be separate zones. The ideal HVAC system is flexible enough to allow for adding or rearranging of zones as use changes. Noise levels should be stable in a range of 30 to 40 NC.

Related post

No comments:

Post a Comment

free counters