RKI Instruments 65-2499RK - Manual (Page 14)

10 • 65-2496RK/65-2499RK CO Detector
Probable causes
• The plug-in sensor has been replaced and the shorting jumper has not been removed.
• The calibration cylinder is low, out-dated, or defective.
• The incorrect calibration cup or regulator is being used.
• The membrane on the detector housing cap is blocked with dirt or some other
particulate contamination.
• The detector is malfunctioning.
Recommended action
1. Confirm that the shorting jumper on the plug-in sensor pins has been removed.
2. Verify that the calibration cylinder contains an adequate supply of a fresh test sample.
3. Confirm that you are using the correct calibration cup and regulator. See “Parts List”
on page 15 for the required calibration cup and regulator.
4. Check the face of the detector housing cap and remove any particulate contamination
from the hydrophobic membrane if necessary. If the membrane appears saturated
with contamination or damaged, replace the membrane as described in “Replacing
the Hydrophobic Membrane” on page 12.
5. If the calibration/response difficulties continue, replace the plug-in sensor as
described later in this section.
6. If the calibration/response difficulties continue, contact RKI Instruments, Inc. for
further instruction.
Unexplained Gas Readings
Symptom
• The display indicates a CO reading when CO is known not to be present.
Probable causes
• The detector needs calibration.
• The charcoal filter on the plug-in sensor is saturated and is no longer scrubbing out
H
2
S or hydrocarbons that cause a response on the CO sensor.
Recommended action
1. Calibrate the detector as described in “Calibration” on page 13.
2. If the difficulties continue, replace the charcoal filter as described later in this section.
3. If the difficulties continue, replace the plug-in sensor as described later in this section.
4. If the difficulties continue, contact RKI Instruments, Inc. for further instruction.
Replacing Components of the CO Detector
This section includes a procedure to replace the plug-in CO sensor, one to replace the
charcoal filter, one to replace the hydrophobic membrane, and one to replace the entire CO
detector assembly. In most cases, it is not necessary to replace the entire detector assembly.
Replacing The Plug-in CO Sensor
CAUTION: The plug-in sensor contains electrolyte which is a dilute acid. Do not disassemble the
sensor when replacing it with a new one. If sensor electrolyte comes in contact with
your skin, wash affected area thoroughly with soap and water.
1. Turn off the controller.