Recirculation; Bunk Override Switch; Sleeper Climate Control Panel - freightliner Columbia Driver Manual

Heater and Air Conditioner

Recirculation

The recirculation mode limits the amount of outside
air entering the cab. Press the recirculation button to
prevent dusty or smoky air from entering the cab.
See Fig. 4.4. The recirculation mode can also de-
crease the time required to cool or heat the cab inte-
rior during extreme outside temperature conditions.
When the recirculation mode is on, the amber indica-
tor on the recirculation button will be on.
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06/21/2001
1. Amber Indicator
Fig. 4.4, Recirculation Button
The recirculation button will not work when the air
selection switch is in one of the following modes:
•
defog mode
•
the selection between defog mode and defrost
mode
•
defrost mode
NOTE: To prevent the buildup of fumes or odors
and to prevent oxygen depletion inside the cab,
the system switches from full recirculation mode
to partial recirculation mode after 20 minutes. In
extremely dusty or smoky conditions, the partial
recirculation mode can be overridden by press-
ing the recirculation button twice to obtain full
recirculation mode. This resets the 20-minute
timer.
Bunk Override Switch, Optional
The bunk override (BUNK OVRD) switch allows the
driver to remotely control the fan speed and tempera-
ture settings in the sleeper. See
upper half of the bunk override switch to override the
sleeper settings with the cab settings. The amber
indicator on the switch is on when the bunk override
4.3
f610504
Fig. 4.1. Press the
mode is on. If the fan speed or temperature setting
on the sleeper climate control panel is adjusted when
the bunk override mode is on, the bunk override
mode will be canceled.
When the heating and air conditioning system is in
the bunk override mode, the cab climate control
panel can be adjusted without affecting the sleeper
settings. To reset the sleeper settings, set the fan
speed and temperature settings on the cab climate
control panel to the desired sleeper settings and
press the upper half of the bunk override switch
again. The cab climate control panel can again be
adjusted without affecting the sleeper settings.
Press the lower half of the bunk override switch to
cancel the override mode. After the override mode is
canceled, the sleeper heater and air conditioner sys-
tem will operate from the sleeper fan speed and tem-
perature settings and the amber indicator will be off.

Sleeper Climate Control Panel

The sleeper heater and air conditioner system fea-
tures Constant Discharge Temperature Control
(CDTC). The sleeper climate control panel is shown
in Fig. 4.5. The CDTC maintains a constant tempera-
ture of airflow in the sleeper regardless of outside air
temperature, selected fan speed, engine coolant tem-
perature, or engine coolant flow. Once the tempera-
ture control switch is turned to the desired tempera-
ture, no other adjustments are necessary.
Fan Switch
The fan switch controls the sleeper heater and air
conditioner system fan speed. The sleeper climate
control panel has eight fan speeds and an off posi-
tion. To increase airflow, turn the switch clockwise or
to a higher number. To decrease the airflow, turn the
switch counterclockwise or to a lower number.
NOTE: When the cab air conditioner is on, the
sleeper fan will operate at low speed even
though the sleeper fan switch is in the off posi-
tion. This is necessary to protect the evaporator
in the sleeper heater and air conditioner system
from freezing.
Temperature Control Switch
The temperature control switch is used to select the
desired temperature in the sleeper. Turn the switch
clockwise or to the red area for warm air. Turn the