Thermo Scientific Thermo Scientific 3906, Operating Manual

Page: 52 / 104

| Handling and Control
8-6
|
Model 3900 Series Thermo Scientific
Chapter 8
Air Exchange Ventilator Caps
Air exchange for the environmental chamber is regulated through the manually adjustable
intake and exhaust ventilator caps located on the top of the cabinet. When viewed from
the front of the environmental chamber, the intake cap is on the left and the exhaust cap
is on the right. The ventilator caps may be opened by turning counterclockwise, and
closed by turning clockwise.
For optimum performance of the unit, the vent caps should be closed at all times.
It might be advisable to open the ventilator caps for specific applications, e.g. for
increased air exchange in insect hatching.
Set Up the Heatless Dryer (Optional)
The optional heatless dryer (P/N 1900139) provides dehumidification for the
environmental chamber (oil removal filter must be installed and an air supply connected -
Chapter 5). The dehumidify switch must be turned On for the dryer to operate. The dryer
is controlled with the humidity controller and will purge dry air into the chamber as needed
to maintain the control set point.
NOTE
Cabinets with factory installed heatless dryers are tested and calibrated at
30°C/30% RH. It is recommended that cabinets are recalibrated when set
parameters are changed to another temperature and/or humidity set point.