Replacing Co2 Sensor And Interface Pcb - Thermo Scientific 3403 Manual

Replacing CO2 Sensor
and Interface PCB
Thermo Scientific
1. Turn the Power switch to "Off " and unplug the power cord from the
wall outlet.
2. Remove the ten (10) #2 Philips
screws that secure the outer rear
wall in place, and remove the first
layer of insulation (see Figure 6).
3. Remove the four nuts that secure
the CO2 sensor mounting plate
and unplug it from the harness.
4. Install the new sensor (PN
290195) in the reverse order.
5. Access the CO2 Sensor Interface
PCB by removing the twelve (12)
screws that secure the side access
cover.
6. Label and disconnect the wiring
interface PCB wiring harnesses.
7. Remove the four #2 Phillips mounting screws and remove the interface
PCB
8. Install the new PCB in the reverse order.
9. Install both covers and all mounting screws.
10. Plug in unit and turn on the main power switch.
11. Allow temperature to stabilize and calibrate the CO2 control
Maintenance and Repairs
Figure 6. CO2 Sensor
Midi 40 CO2 Incubator
Section 6
6-3