ENMET PROAIR 2200 - Manual (Page 27)

P RO A IR 2200 ENMET Corporation
24
5.4 Sensor Replacement
5.4.1 Gas Sensor
A Gas sensor must be replaced when it can no longer be calibrated. To replace a sensor, perform the following steps.
Turn off the electrical power. The sample air can continue to flow.
Open the display panel and remove the four manifold retention screws and remove the manifold. See Figure 9.
Remove the old sensor, and replace it with a new sensor.
C AUTION : Some new sensors come with a shorting clip that must be removed before installation, for proper operation. See
Figure 8.
Replace the manifold.
Turn on the electrical power.
Recalibrate the sensor per the instructions in Section 5.3. Recalibrate the sensor and again 1 month after replacement.
5.4.2 Oxygen Sensor
An oxygen sensor must be replaced when it can no longer be calibrated in clean air. To replace the sensor, follow the general
steps given for the replacement of a gas sensor, but effect a replacement of the oxygen sensor. After sensor installation, wait
four hours before re-calibrating, and again 1 month after replacement.
Figure 9: Location of Gas Sensor and Dew Point Manifolds
5.4.2 Calibration/Sensor Replacement for CO, O
2,
HC and CO
2
(Gas Channels)
Calibration is the process of setting the instrument up to read accurately when exposed to a target gas. This is a two step
process. A Low Calibration sets clean air reference point and the High Calibration function sets the sensitivity of the
instrument. Proper calibration requires that these two steps be preformed and successfully completed.
Calibration equipment is available from ENMET Corporation to calibrate the P RO A IR 2200 . A list of needed material is in
Section 7.0. A calibration adapter will have a fitting for the gas cylinder on one side, and a quick-disconnect to attach to the
instrument on the other.
You may exit the calibration section, at any time, by pressing and holding the OPTION switch for 3 seconds, if entering
calibration section by mistake or calibration gas is not available.
N OTE : Exiting the calibration process before successfully completing the necessary two steps returns the instrument to the last
point of calibration.
Wait 24 hours after initially supplying air and power to the P RO A IR 2200 sensor before initial calibration. It is not necessary to
open the Front Panel to make adjustment. The calibration functions are operated through the OPTION and SELECT switches on
the front panel.
Dew Point Probe Manifold
Retaining Screw, 2 places
Gas Sensor Manifold
Retaining Screw, 4 places
Remove Shorting Clip
from Cell if Present
Bottom View of Sensor
Figure 8: Shorting Clip
Ref: Orifice & Pre-filter
MOS
Sensor CO2