Thermo Electron 3940 Series, Operating And Maintenance Manual

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4-2 Model 3940 Series Thermo Electron Corporation
Section 4
Service
Humidity/Temp
Sensor
6. Pull the probe up through the access hole and into the control panel.
7. Follow the wires from the probe to the thermostat mounted on the
control panel. Clip the plastic ties holding the overtemp cable to the
existing wiring.
8. Pull the overtemp knob on the control panel off.
9. Remove the two screws that hold the overtemp assembly to the control
panel.
10. Disconnect the two wires from the back of the thermostat assembly.
11. Pull the entire assembly from the panel, and remove the unit.
12. Replace the thermostat and probe.
13. Re-assemble in reverse order.
Note
Reseal probe access hole with Permagum and tie-wrap overtemp
cable to existing wires after replacing probe.
V
1. Follow instructions 1-6 from ‘Over/Undertemp Probe and Thermostat’
section to locate and remove the probe from the chamber.
2. Clip any plastic ties securing the probe wiring. Disconnect the probe.
3. Install the replacement probe in the chamber. When replacing the
humidity sensor, be sure to mount the probe at the same angle as
originally mounted.
4. Route the probe wire through the access hole into the control housing.
5. Connect the probe to the appropriate controller wiring.
6. Reseal the probe access hole with Permagum and tie-wrap the probe
wire to existing wires.