Replacing The Temperature Sensor - Thermo Scientific 3403 Manual

Section 6
Maintenance and Repairs
Replacing the
Temperature Sensor
6-2 Midi 40 CO2 Incubator
The temperature sensor (PN
290194) should be replaced if it
no longer matches the
Temperature vs. Resistance chart
in the Appendix.
1. Turn the Power switch to
"Off " and unplug the power
cord from the wall outlet.
2. Open the glass door and
remove knurled thumb nut
securing the sensor bracket.
3. Remove the ten (10) #2
Philips screws that secure the
outer rear wall in place, and
remove the first layer of
insulation.
4. Locate the temperature sensor
cable and break the silicone
seal where the sensor enters the
cabinet. Pull sensor from the
chamber.
5. Unplug the sensor from the
Main Control PCB connector
J6 and withdraw it from the
cabinet.
6. Install the new sensor in the
reverse order.
7. Use 100% silicone to seal the
opening where the sensor
enters the chamber.
8. Calibrate the temperature
control in accordance with the
Temperature Calibration
procedure in this section.
Figure 6-2. Temp Sensor (viewed from
inside the chamber)
Figure 6-3. Outer Rear Wall Removed
Figure 6-4. Temp Sensor Connector
Thermo Scientific