RKI Instruments EAGLE 2 Manual - Manual (Page 246)

236 • Maintenance EAGLE 2 Operator’s Manual
Maintenance
This section includes a procedure for replacing an infrared CO
2
sensor.
Replacing the IR CO
2
Sensor or Changing Sensor Type
1. Verify that the EAGLE 2 is off.
2. Place the EAGLE 2 upside down on a flat surface or hold it upside down.
3. Unscrew the three case screws until they disengage from the top case.
They are captive screws so they will not fall off of the bottom case.
4. Turn the EAGLE 2 right side up and carefully lift the top case away from
the bottom case. Be careful not to lift it so far that it pulls on the main
PCB with the cable that connects the top case to the main PCB.
5. Lay the top case down next to the bottom case to allow access to the flow
system.
6. Locate the infrared CO
2
sensor. It has a twelve wire cable with a
connector that mates to an infrared sub PCB that is installed on the main
PCB and is normally located next to the pump. Figure 38 on page 224
shows an infrared CO
2
sensor in a typical location.
7. Unscrew and remove the two screws that hold down the infrared CO
2
sensor bracket.
8. Grasp the sensor firmly and pull it out of the infrared CO
2
flow chamber.
Rock it back and forth gently if necessary to pull it out. Take care not to
pull the cable from the sub PCB.
9. Rotate the locking lever counterclockwise on the cable connector that
mates to the infrared CO
2
sensor to unlock it.
10. Unplug the old infrared CO
2
sensor from the cable.
11. Connect the new infrared CO
2
sensor to the sensor cable and rotate the
locking lever clockwise to lock the connector.
12. Insert the sensor into the infrared CO
2
flow chamber and push it in until it
bottoms out.
13. Line up the holes in the infrared CO
2
sensor bracket with the two
standoffs on the infrared CO
2
chamber.
14. Install the two sensor bracket screws.
15. Confirm that the main PCB is seated in its slots and that its bottom edge
is resting on the bottom of the bottom case. If the main PCB is not seated