will then be shown in the display. To change the tempera-
ture, press the UP or DOWN arrow key. The adjustable
temperature range is 0 to -30°C (32 to -22°F). When the
desired set temperature is displayed, press the Menu key-
pad to enter the set temperature and activate the Units
Select menu.
Units Select
The second menu selects the units. The freezer control
displays temperature in °C or °F. The factory setting is
°C. Starting from the temperature display mode (Mode
LED off), press the Menu key twice. The current temper-
ature units are displayed. To switch between units, press
the UP or DOWN arrow key to change to the desired
units, then press the Menu key to select. The desired
unit LED will be displayed on the right of the temperature
display.
Calibration Offset
In the event the freezer needs calibrated, a simple routine
is available to adjust the display and control point to a ref-
erence standard. To set the temperature offset, press
and hold the Menu keypad for 5 seconds. The display
will flash oS (offset) followed by the last temperature off-
set value. The factory setting is 0. To change the offset
value, press the UP or DOWN arrow key, then press the
Menu key. The value shown in the display will be added
to the previous temperature reading. The maximum off-
set value is ±5°C (±9°F).
For Example:
The freezer has been operating at -15°C for 30 minutes.
The display indicates -15°C but a reference thermometer
in the refrigerator chamber indicates -17°C. The operator
presses and holds the Menu keypad for 5 seconds and
changes the offset value from 0 to -2. The Menu key is
pressed again. Now the display indicates a chamber
temperature of -17°C and the system begins to control to
the desired temperature of -15°C (as long as the 3 min.
time delay has expired).
Allow an additional 30 to 40 minutes for the freezer to
again stabilize. If the display is still inaccurate, repeat the
Calibration Offset procedure.
8
O
PERATION
