– 21 –Normal Operating Characteristics
•Evaporator fan running, without compressor or
condenser fan.
•Liner Protection Mode, fan comes on when the
doors are open for 3 minutes.
•Different sound levels can be heard when the
fan changes speed; however, the fan should
never be heard oscillating between speeds.
•Response time for drastic temperature change
is 2 to 10 minutes. The main control board will
only respond to 8 °F of temperature change
per minute as determined by resistance of
sensor.
Abnormal Operating Characteristics(Incorrect Operation)
•Rapid fan speed changes, fan takes at least
1 minute to change speeds.
• Compressor running without the condenser
fan. The compressor and condenser fan
should always run at the same time.
Liner Protection Mode
The liner protection mode will activate if either of
the doors has been open for 3 minutes. This
mode will start the evaporator fan on high speed.
This mode is controlled by 2 timers. Timer #1
monitors door-open time. A 3-minute door-open
count begins when the door is opened. If
3 minutes elapse before the door is closed, the
liner protection mode will become active. Once
the door is closed, timer #1 resets and liner
protection mode goes into standby. In standby ,
normal fan and damper operations resume and
timer #2 begins a 3-minute door-closed count.
If 3 minutes elapse without a door opening, liner
protection mode will completely deactivate. If a
door is opened within the timer #2 door-closed
count, the remaining time in the door-closed count
will be deducted from the timer #1 door-open
count.