Mazda Training manual — part 272

Air Conditioning Fundamentals

TC070-05-01S

9 – AIR DISCHARGE
MANAGEMENT

62

OBJECTIVES

After completing this section, you will be able to describe how the following components
direct airflow through the heating and A/C system:

•

Fresh/re-circulated air door

• Blower

fan

•

Temperature blend door

• Defroster

door

•

Vent/face and heater doors

Air Conditioning Fundamentals

TC070-05-01S

9 – AIR DISCHARGE
MANAGEMENT

63

FIGURE 31. The
Mazda climate
control system
allows the operator
to select heating or
cooling, with the
conditioned air
directed to various
vents on the
dashboard.

AIR FLOW MANAGEMENT COMPONENTS

The climate control system in Mazda vehicles provides conditioned air
at the desired temperature. It is a combined heating and air conditioning
unit. The operator can select heating or cooling and direct the air to
specific vents on the dashboard. Figure 31 shows the location of these
vents in a typical vehicle.

The heating and A/C system provides a desired comfort zone in the
passenger compartment by controlling temperature and humidity. This
comfort zone is subjective, varying from person to person. In addition,
as weather conditions change, the system must allow changes in
temperature and airflow direction.

Front heat

Front heat

Rear heat

Rear heat

Side vent

Center Vent

Defroster Defroster

Side demister Side demister

Side vent

Air Conditioning Fundamentals

TC070-05-01S

9 – AIR DISCHARGE
MANAGEMENT

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To allow this flexibility, the system includes the following airflow
management components:

•

Fresh/re-circulated air door

• Blower

fan

•

Temperature blend door

• Defroster

door

•

Vent/face and heat doors

The following topics describe the operation of these components.

Fresh/Re-circulated Air Door

Air first enters the system through the fresh/re-circulated air door, as
shown in Figure 32.

FIGURE 32. The
fresh/re- circulated
air door allows
either outside air or
re-circulated air
from the vehicle
interior into the
heating and A/C
system.

Heater

Evaporator

Door

Recirculated air

Fresh air

Air Conditioning Fundamentals

TC070-05-01S

9 – AIR DISCHARGE
MANAGEMENT

65

FIGURE 33. The

blower fan draws air

through the fresh/re-

circulated air door for

cooling and/or

heating.

If the operator selects the fresh air option, the system draws outside air
into the unit either by the force of the forward motion of the vehicle or
with the assistance of a fan. During normal operation, the fresh air
option provides the best results.

The re-circulated air option closes off the outside air passage and
re-circulates cool, dehumidified air from the passenger cabin. This
option provides maximum cooling.


Blower Fan

The blower fan, highlighted in Figure 33, draws air in through the fresh/
re- circulated air door. Depending on the system settings, the blower
draws air through the evaporator (for cooling), the heater unit, or a
combination of both.

Heater Evaporator

Blower fan