Replacing the air filter – RKI Instruments Digester Gas Monitor User Manual
Page 90
84 • Replacing the Air Filter
Digester Gas Monitor Operator’s Manual
9.
Reinstall the preamp circuit board with the sensor onto the flow block.
10. Turn the regulator knob clockwise to set the sensor flow to 3 SCFH when you restart
the system.
11. Turn on incoming power.
12. Calibrate the replacement sensor as described in “Performing a Calibration” on
page 63.
Replacing the CO
2
Sensor
1.
Turn off the Digester Gas Monitor.
2.
Turn off incoming power to the Digester Gas Monitor.
3.
Open the housing door of the Digester Gas Monitor.
4.
Turn the regulator knob all the way counterclockwise to close the regulator output.
5.
The CO
2
sensor and preamp are located in the upper left corner of the flow block
when viewed from the top. Unscrew the 4 screws that retain the preamp circuit board.
Take care not to lose the flat washer and lock washer under each screw head.
6.
Lift the preamp circuit board away from the flow block.
Be careful not to pull on the cable that connects the preamp circuit to the main circuit
board.
There is a gasket in the bottom of the sensor cavity. Make sure the gasket stays in
place.
7.
Pull the CO
2
sensor off the preamp circuit board.
8.
Plug the new sensor into the preamp board.
9.
Reinstall the preamp circuit board with the sensor onto the flow block.
10. Turn the regulator knob clockwise to set the sensor flow to 3 SCFH when you restart
the system.
11. Turn on incoming power.
12. Calibrate the replacement sensor as described in “Performing a Calibration” on
page 63.
Replacing the Air Filter
This section describes how to replace the air filter.
1.
Turn off the Digester Gas Monitor.
2.
Turn off or unplug power to the Digester Gas Monitor.
3.
Open the housing door of the Digester Gas Monitor.
4.
Turn the regulator knob all the way counterclockwise to close the regulator output.
5.
Locate the air filter. It is in the bottom right corner of the housing.
6.
Grasp the air filter and remove it from the tubing on each end.
7.
Place the new air filter in the same orientation as the one that was removed and
connect the tubing to each end of it. The arrow on the air filter should be pointing up,
away from the Fresh Air Inlet fitting.
8.
Turn the regulator knob clockwise to set the sensor flow to 3 SCFH when you restart