Classification of Ventilation Systems

It is common to classify ventilation systems by functions, distribution strategies, ventilation principles - or by combinations of them all.

Classifying by Function

It is common to classify a ventilation system by function:

• Ventilation - Supply and evacuating of air with the main purpose to keep the atmospheric climate according the requirements
• Climate - Supply and evacuating air with main purpose to keep the temperature and the atmospheric climate according requirements
• Heating or cooling - Recycling system with the main purpose to supply the building with necessary heat or cooling
• Combined system - The functions above more or less combined in one system

Classifying by Distribution

A ventilation system can also be classified by distribution:

• Centralized - A central plant supplies and extract air to and from the whole building
• Decentralized - Each room/area of the building has it's own ventilation unit
• Combined - Both centralized and decentralized systems used

Classifying by Ventilation Principle

A ventilation system can also be classified by the ventilation principle and air flow:

• Displacement air flow through the room - CAV (Constant Air Volume) or VAV (Variable air volume
• Mixed air flow through the room - CAV (Constant Air Volume) or VAV (Variable air volume.

Examples of Ventilation Systems Classifications

• Single-Zone Constant-Volume System
• Single-Zone Constant-Volume System with Reheating
• Multi-zone System
• Induction Unit System
• Variable-Air-Volume System
• Dual-Duct System

Temperature ^oC
K
^oF

Length m
km
in
ft
yards
miles
naut miles

Area m²
km²
in²
ft²
miles²
acres

Volume m³
liters
in³
ft³
us gal

Weight kg_f
N
lbf

Velocity m/s
km/h
ft/min
ft/s
mph
knots

Pressure Pa
bar
mm H₂O
kg/cm²
psi
inches H₂O

Flow m³/s
m³/h
US gpm
cfm