24 • 35-3001A-01-XX1 Sample-Draw Detector Operator’s Manual
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:
a) Disconnect the tubing routed to the sampling area, if installed, from the particle filter.
b) Disconnect the particle filter from the tubing stub.
c) Install the new particle filter onto the tubing stub. Be sure the arrow on the particle
filter is pointing toward the inlet fitting.
d) Reinstall the tubing routed to the sampling area.
4. If the particle filter is installed at the end of the inlet line:
a) Remove the particle filter from the tubing stub.
b) Install the new particle filter onto the tubing stub. Be sure the arrow on the particle
filter is pointing toward the inlet line.
5. Turn on power to the controller.
6. Turn on the controller.
Adjusting the Low Flow Setting
NOTE:
Adjusting the low flow setting will cause a low flow alarm at the sample-draw
detector and a fail alarm at the controller. Be sure to put the controller into its
calibration program or disable external alarms before performing this test.
The factory-set low flow setting is 0.6 SCFH (±0.1). To adjust the low flow setting:
1. Use the sensor flow control valve to set the flow to 0.6 SCFH. Turn the valve’s knob
counterclockwise to increase the flow and clockwise to decrease the flow.
If the sample-draw detector goes into low flow alarm before you can adjust the flow down
to 0.6 SCFH, adjust the pressure switch adjustment screw 1/4 turn clockwise, then attempt
to set the flow again. Repeat this step until you are able to adjust the flow to 0.6 SCFH.
NOTE:
The pressure switch adjustment screw is accessible through a circular cutout in the
flowmeter circuit board.
