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Sensor Cleaning
1.
Unscrew the sensor cap.
2.
Pull the sensor straight out, using a slight rocking motion if
necessary.
3.
Put the sensor into a beaker and cover it with pure methanol
or ethanol.
4.
Put the beaker into an ultrasonic cleaning bath and sonicate
for 15 minutes. Then take out sensor and dry it. Shake the
sensor vigorously to remove excess liquid and if possible,
use a gentle stream of clean air to blow the residual liquid out
of the sensor.
5.
Always re-calibrate the PID after cleaning the sensor.
Sampling Pump
The flow rate should be roughly 250-350 cc/min at low pump speed and 350-450 cc/min at high
pump speed when there is no air leakage (and no tube in the holder). When approaching the end of
its useful operating life, the pump will consume more energy and draw significantly lower flow.
Also, if excessive dust or particles enter the pump, the flow will be reduced. A strong pump should
stall and/or nearly stop when a finger is used to block the inlet. If the pump does not stall but the
flow is weak, it is likely that particles are trapped in the pump diaphragm. When this occurs, it is
necessary to replace or rebuild the pump, or clean the diaphragm. Repair of the pump requires
removal of the circuit board and must be done by an authorized service center.
