Comfort Environments - Selecting Ventilation System
A quick selection guide of ventilation system in comfort environments.
The cooling capacity of an air-condition system is often determinant for selecting the type and the principle, and the capacity is often limited by comfort requirements.
Maximum capacities for displacement and mixing systems in different kind of buildings are roughly indicated below.
Type of building | Ventilation system | Ventilation principles and Cooling loads (W/m2) | |
---|---|---|---|
Mixing | Displacement | ||
Offices | CAV | 0 - 20 | 10 - 30 |
VAV | 20 - 60 | 20 - 60 | |
Fan-coil | 40 - 70 | ||
Cooling ceiling | 60 - 100 | 60 - 100 | |
Hotels | CAV | 0 - 20 | 10 - 30 |
VAV | 20 - 50 | 20 - 50 | |
Fan-coil | 20 - 50 | ||
Hospitals | CAV | 0 - 20 | 10 - 30 |
VAV | 20 - 60 | 20 - 60 | |
Cooling ceiling | 60 - 100 | 60 - 100 | |
Public buildings | CAV | 0 - 20 | 10 - 30 |
VAV | 20 - 60 | 20 - 60 | |
Department stores | CAV | 0 - 20 | |
VAV | 20 - 80 | ||
Fan-coil | 40 - 100 |
The heat load in typical rooms are influenced by the use of lights, heat emission from machines like computers, the number of people and the sun radiation through windows and other building elements. The heat load is typically very dynamic and for larger building and systems some kind of computerized tools are helpful in the designing process.
Heat loads in some typical rooms are indicated below:
Typical rooms and heat loads | Heat Load (W/m2) |
---|---|
Normal offices without automatic | 0 - 30 |
Normal offices with automatic | 30 - 50 |
Conference rooms | 20 - 75 |
Data rooms | > 60 |
Guest rooms, normal standard | 0 - 25 |
Guest rooms, high standard | 25 - 50 |
Patients rooms | 0 - 20 |
Treatment rooms | 20 - 60 |
Intensive rooms | > 50 |
Conference rooms | 20 - 75 |
Theater, cinema | 40 - 60 |
Restaurants | 30 - 70 |
Class rooms | 20 - 50 |
Food | 20 - 40 |
Normal | 30 - 60 |