User's Manual

Isotempâ Laboratory and Chromatography Refrigerators
Page 6 of 12
Part Number: 104416
Temperature
Controller
Setting the Temperature
Units Select
Calibration Offset
Begin operation by inserting the key into the key switch located on the
header panel. The key switch is packed inside the envelope, which is
shipped in the refrigerator chamber. Turning the key switch to the ON
( | ) position will energize the evaporator fans and the digital
controller.
The digital temperature controller is located on the left side of the
header panel (See Figure 4). When the unit is initially turned on, the
display will indicate current chamber temperature. The temperature
units will be indicated by the °C or °F LED located just to the right of
the temperature display. The refrigerator is factory set at 4°C. When
the unit is first energized the evaporator fans will operate however it
will not immediately cool. A 3-minute compressor delay is
programmed into the controller to provide sufficient time for the
evaporator to defrost and to allow the system pressure time to
equalize. When the delay time is over, the Cool LED will illuminate,
the compressor will run and the chamber will cool.
NOTE: The compressor requires a 3-minute delay time
between activations. The unit will not cool during this
delay. The delay is also activated when the controller
is first energized.
To change the set temperature, press and release the Menu keypad
once. The display will flash SP and the Mode LED will be illuminated.
The last set temperature will then be shown in the display.
To change the temperature, press the UP or DOWN arrow key. The
adjustable temperature range is 1 to 12°C (34 to 54°F). When the
desired set temperature is displayed, press the Menu keypad to enter
the set temperature and activate the Units Select menu.
The second menu selects the units. The refrigerator 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 temperature units are displayed. To switch between
units, press the UP or DOWN arrow key then press the Menu key to
select. The unit LED will be displayed on the right of the temperature
display.
In the event the refrigerator needs to be calibrated, a simple routine is
available to adjust the display and control point to a referenced
standard. To set a temperature offset, press and hold the Menu
keypad for 5 seconds. The display will flash oS followed by the last
temperature offset 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 display will then flash Ho.