Facilities Management and Design

1
Facilities Management and Design

• Chapter 7
• HVAC Systems

2
Thermal Comfort

• Balancing heat produced by ones body with
  surrounding environment.
• Body heat lost by convection, radiation, and
  evaporation

3
Factors that influence comfort

• indoor temperature
• humidity
• air movement
• room surface temperatures
• overall air quality

4
Comfort zone

• Insert comfort zone chart

5
Heat sources

• Electricity Used in all electric heaters.
  Requires no flue. Usually most expensive.
• Natural gas Clean burning. Flue required. Very
  efficient. Delivered via underground pipe
• Liquefied petroleum relatively clean burning.
  Requires on-site storage tank. Delivered via
  truck.
• Fuel oil tendency to create dirt/smoke.
  Requires on-site storage tank. Delivered via
  truck. Various grades available.
• Steam more common in urban areas where
  available from local utility or in large
  complexes with central steam plant. Supply and
  return lines required.

6
Heating equipment

• Furnaces and Boilers
• Combustion efficiency

Flue
Furnace
Heat Exchanger
7
Cooling Systems

• Boyles Ideal Gas Law
• Pressure
• Temperature
• Volume
• Certain gases react more actively
• Refrigerants
• CFCs
• HCFCs

8
The Refrigeration Cycle
Compressor
Evaporator Coil
Condenser Coil
Expansion Valve/ Metering Device
9
Cooling system operating and maintenance concerns

• Types of compressors
• Reciprocating
• Centrifugal
• Rotary
• Energy efficiency ratio (EER)
• Integrated part load values (IPLV)
• Environmental Protection Agency
• supervises aspects of refrigeration equipment
  maintenance
• importance of eliminating or reducing refrigerant
  leaks

10
Cooling system operating and maintenance concerns

• Types of compressors
• Reciprocating
• Centrifugal
• Rotary
• Energy efficiency ratio (EER)
• Integrated part load values (IPLV)
• Environmental Protection Agency
• supervises aspects of refrigeration equipment
  maintenance
• importance of eliminating or reducing refrigerant
  leaks

11
HVAC system types

• Centralized systems quiet
• two-pipe
• three-pipe
• four-pipe
• Decentralized systems not as quiet
• heating and cooling sources in guestroom itself
  or along outside wall
• Hybrid systems
• characteristics of centralized and decentralized
  systems

12
System types and maintenance needs of HVAC
systems for other building areas

• Air handling units
• Isolation of zones (housekeeping, kitchen,
  maintenance)
• Packaged air conditioning units
• usually mounted on roof
• Maintenance issues
• Filter replacement
• belt checking and replacement
• cleaning of fans and heat transfer surfaces

13
HVAC controls

• Todays controls are often electronic
• Thermostat
• enthalpy or economizer control
• Older control sensorsmechanical sensing
• Digital control systems
• variable air volume (VAV) systems
• load sensing equipment
• EMS sensors

14
Cooling towers

• Startup and shutdown concerns
• Inspection and lubrication of pumps and fans
• Removal of dirt and other debris
• Treatments to reduce bacteria, scale, and
  corrosion
• Inspection of metal surfaces