HVAC Systems

1
HVAC Systems Primary Functions

• Temperature Control
• Cooling
• Heating
• Humidity Control
• Humidification
• Dehumidification
• Air Quality Control
• Ventilation
• Cleaning

2
Typical Energy Use in a Commercial Building
HVAC Systems Energy Considerations
3
Efficient Use of Energy Requirements
HVAC Systems

• Optimum Energy Designs

• Well-Developed Energy Use Policies

• Dedicated Management backed up byProperly
  Trained and Motivated Operating Staff

4
Minimum Guidelines in Energy Conservation, Design
and Operation
HVAC Systems
ASHRAE Standard 90.1-1989, Energy Efficient
Design of New Buildings Except Low-Rise
Residential Buildings
ASHRAE Standard 100, Energy Conservation in
Existing Buildings
5
Typical Building Design Heat Losses or Gains
HVAC Systems
6
Some Relevant Energy/Emissions Statistics
HVAC Systems
Buildings account for 36 of all the energy 66
of all the electricityused in the US
Emissions related to building energy use account
for 35 of CO2 emissions 47 of SO2
emissions 22 of NOx emissions
7
Annual Energy Use Per Unit Floor Area
HVAC Systems
8
Capital Cost Estimating Factors
HVAC Systems
9
Schematic of a Typical Commercial
Air-Conditioning System
HVAC Systems
10
Elementary Air Temperature Control System
HVAC Systems
11
Air Handler and Associated Controls for Simple
Constant-Volume, Single-Duct All-Air System
HVAC Systems
12
Schematic of a Blow-Through Air Handler With Hot
and Cold Decks and Zone Dampers
HVAC Systems
13
Simplified Control Schematic for a
Constant-Volume reheat System
HVAC Systems
14
Simplified Control Schematic of a Single-Duct VAV
System
HVAC Systems
15
Simplified Control Schematic of a Dual-Duct System
HVAC Systems
16
Multi-Zone System With Hot and Cold Plenum Reset
HVAC Systems
17
Air-Water Induction Unit
HVAC Systems
Typically installed at perimeter wall under
window or overhead
From Central A/C Unit
Hot or Chilled Water
18
Typical Fan-Coil Unit
HVAC Systems
Chilled Water or Brine/ Hot Water or Steam or
Electric Heater
Air-Conditioned Air
Recycles Room Air, Cheapest Perimeter System,
Ventilation Provided Separately
19
Typical Air-Conditioning Ventilator with Separate
Coils
HVAC Systems
20
Schematic View of a Room Air-Conditioner
HVAC Systems