Chapter
12
Air Delivery
Systems
185
Copyright by Goodheart-Willcox Co., Inc.
After studying this chapter, you will be able to:
Explain how an HVAC system blower operates.
Identify the major parts of an HVAC system blower and motor.
Explain the operation of HVAC blower speed controls.
Identify the purposes of HVAC system air ducts.
Explain the design and placement of HVAC system air ducts.
Identify the types and purposes of HVAC system air doors.
Explain how HVAC system air doors are operated.
Identify and explain HVAC system air door operating devices.
Air handling system
Upstream
Downstream
Blower wheel
Squirrel cage blowers
Blower motor
Resistor pack
Blower relay
Afterblow module
Air ducts
Ductwork
Plenums
Intake ductwork
Evaporator cases
Heater cases
HVAC modules
Split case
Modules
Independent cases
Output ductwork
Vents
Registers
Independent vents
Air doors
Blend door
Temperature door
Diverter doors
Mode doors
Air conditioning-heater door
Heater-defroster door
Recirculation door
Air inlet door
Heater restrictor door
Dual Zone
Air bypass door
Upper and lower mode doors
Cables
Lever
Vacuum diaphragms
Vacuum motors
Stepper motors
Cabin fi lters
Evaporator water drain
Technical Terms