Atmospheric Technology
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7. Maintenance
This section describes routine maintenance procedures for the Model 8001 Canister
Sampler. All other repair work should be performed by trained personnel.
7.1 Pressure Pump
To remove the pressure pump from the sampler, remove the top cover. Remove the
inlet tube and disconnect the electrical connector. Remove the screws attaching the
pump mounting bracket to the sampler and remove the pump.
The pump diaphragm can be replaced by removing the four screws on the top of the
pump. Grasp the diaphragm and turn it counter clockwise to unscrew if from the
connecting rod.
7.2 Canister Filter
The operator should periodically replace the 2 micron (7 micron for pressurized
sampling) sintered stainless steel filter in the canister flow path. The filter must be
replaced when the canister flow rate cannot be maintained. Site conditions will
determine the replacement frequency. Remove the reducing fitting at the inlet and
use a small punch or rod to push the pressed-in filter disk out the end of the fitting
and replace with a new disk. The new filter disk may need to be tapped into the
fitting with a clean hammer.
7.3 Mass Flow Controller Calibration
Each mass flow controller should be calibrated on an annual schedule. The mass
flow controllers can be calibrated either electronically or manually. Manual
calibration consists of adjusting the zero (no flow) and span potentiometers using a
reference flow standard. The potentiometers can be accessed on the side of the
flow controller housing. Electronic calibration can be performed by inserting the
appropriate calibration constants into the advanced portion of the setup screen.
Appendix A provides a worksheet to calculate these constants using a calibrated
flow reference standard.
