1.3.1 Column heater/cooler operation
The 30-cm CHC module is a combination forced-air convection heater and cooler. When the
compartment temperature is set, either directly from the console or within a method, a command
is sent to the column heater/cooler to switch the compartment heating element on or off. On the
basis of feedback from the compartment thermistor, the thermoelectric device continues to heat,
or cool, until the compartment achieves the specified temperature set point.
Recommendation:
When sample and column temperature are important to an application, in
addition to specifying explicit temperature set points in the method, specify appropriate
temperature limits. Together, these settings ensure that system operation occurs only within the
defined limits and that any occurrence of an unacceptable deviation from the set points is flagged
by an error message acknowledging the variance.
1.4 Column-selection valve kit option
When the 30-cm CH or 30-cm CHC module is fitted with the optional column-selection valve, the
valve is installed within the module's column compartment.
Note:
A bio-compatible column-selection valve is available for 30-cm CH and 30-cm CHC
modules installed in Bio systems.
Figure 1–4: Column-selection valve assembly
Valve bracket
Captive screws (2)
Column-selection valve
December 5, 2017, 715004751 Rev. C
Page 16