Thermo King 098916, Maintenance Manual

Page: 87 / 196

Operating Instructions
86
Vent Door Assembly
A microprocessor controlled vent door provides
programmable control of the air exchange rate.
The vent door is adjusted to the desired position
by a vent door motor and linkage assembly,
shown in Figure 46. The system is pre-calibrated
for air exchange rates of 0 to 280 m
3 /hr. (0 to
165 ft 3 /min.). The use of the AFAM system
should be established by the shipper.
The default setting for AFAM in the Setpoint
menu is the last value set (Off, Units, Demand, or
Manual). The AFAM submenu should be set to
Units to control the vent door to the fresh air
exchange rate setting.
If the controller identifies a component failure
during unit startup, an alarm is recorded in the
controller display and data-logger memory. If a
power loss occurs after the AFAM system is
turned on, the controller automatically operates
the vent door based on the previous AFAM Delay
and AFAM Rate settings when power is restored.
WARNING: After installing or servicing
the AFAM door, remove all tools and
install the vent grille before starting the
AFAM system. Failure to replace the vent
grille before turning the AFAM system on
may result in personal injury or unit
damage.
Alarm
Code Alarm
Type
Description
57 Check
AFAM Control Module or Motor Error:
Indicates a frozen or stuck vent door
or a problem with the control module
or its wiring or the motor current draw
is not with limits.
1. Cotter Pins
2. Shoulder Washer
3. Pin
4. Rod End
5. L-Rod
6. Vent Motor Linkage
Figure 46: Vent Door Linkage Adjustment