Maintenance • 25
There is a gasket at the bottom of the flow block. Be sure the gasket stays in place.
6. Disconnect the sensor from the CO amplifier.
7. Plug the CO sensor into the new CO amplifier.
8. Place the sensor and amplifier in the CO sensor cavity.
9. Secure the CO amplifier on the flow block with the two screws you removed in step 5.
10. Reconnect the wires coming from the CO amplifier to the AMP 2 position on the detector/
amp terminal strip.
Connect the red wire to the “+” terminal. Connect the blue wire to the “S” terminal.
NOTE:
When the sample-draw detector is first powered up with a new amplifier, the initial
output may be either high or below zero depending on the setting of the span pot. Be
sure to make arrangements so that this does not cause unwanted alarms.
11. Turn on power to the controller.
12. Turn on the controller and place it into normal operation.
13. Allow the sample-draw detector to warmup for 5 minutes.
14. Calibrate the sample-draw detector as described in “Calibration, CO Sensor” on page 30.
Replacing the Hydrophobic Filter
1. Turn off the controller.
2. Turn off power to the controller.
3. Open the housing door of the sample-draw detector.
4. Disconnect the filter from the rubber elbows on each end of the filter, then remove the
filter from the sample-draw detector.
5. Install the new filter. Be sure the side of the filter marked “INLET” is connected to the
elbow that is connected to the inlet fitting.
6. Turn on power to the controller.
7. Turn on the controller.
8. Verify that the flow rate is approximately 1.0 SCFH, then close the housing door.
Replacing the Particle Filter
1. Turn off the controller.
2. Turn off power to the controller.
3. If the particle filter is installed at the inlet fitting, perform the following:
a) Disconnect the tubing routed to the sampling area, if installed, from the particle filter.
