15
OPERATING INSTRUCTIONS
Control panel
Temperature display
The unit is set at the factory to obtain the proper temperature automatically (4
o
C 1
o
C).
The high temperature alarm is preset at 6
o
C. The low temperature alarm is preset at 2
o
C.
Table 1. Temperature display : Lamp ON : Lamp OFF
Operation Key operated Display Display mode
1 Plug-in, Power ON
Average monitor bottle
temperature
UPPER
LOWER
Average temperature
2 Press key.
Upper monitor bottle
temperature
UPPER
LOWER
Upper temperature
3 Press key.
Lower monitor bottle
temperature
UPPER
LOWER
Lower temperature
4 Press key.
Average monitor bottle
temperature
UPPER
LOWER
Average temperature
5 Repeat from 2
Note:
The displayed temperature represents the temperature sensed by a thermal sensor attached to the
monitor bottles mounted to the upper and lower portion of the chamber.
The displayed temperature may not always be at 4
o
C. The chamber probes are representative of high
and low average temperatures within the chamber.
Defrost cycles
There is no need for routine defrosting of the unit as this occurs automatically as follows:
1. Cycle defrost
To keep the chamber temperature stable, the refrigeration compressor is cycled on and off. During “off”
period any frost which has accumulated on the evaporator is melted by energizing a defrost heater. This
will not have any discernible effect on the chamber temperature.
2. Forced defrost
When the ambient humidity is high, or a large amount of damp product is being stored inside the chamber,
there is a possibility that cycle defrost may not be enough to remove all of the frost on the evaporator. In
this case, a forced defrost cycle can be initiated.
When the unit is operating under a forced defrost cycle, the current chamber temperature and “dF” is
displayed alternately on the digital temperature display.
Once the forced defrost cycle is completed, normal operation resumes.
The chamber temperature of blood bag (400mL) rises about 1 to 2
o
C during the defrosting.
UPPER
LOWER
UPPER
LOWER
UPPER
LOWER
UPPER
LOWER
UPPER
LOWER
UPPER
LOWER