35-3001-06H-DIL Hydrogen/Oxygen Sample-Draw Detector • 15
Recommended action
1. At the sample-draw detector, set the correct sensor flow rate with the sensor flow control
valve.
2. Connect a 0-2 SCFH flowmeter to the inlet fitting or the inlet line and confirm the flow is
above the low flow setpoint of 1 SCFH while holding down the reset switch.
NOTE:
RKI Instruments, Inc. offers a 0 -2 SCFH flowmeter but tubing connection fittings must
be user installed to the flowmeter’s 1/8” NPT female fittings.
3. If you cannot set the correct sensor flow rate or confirm a good sample flow, check the sample
lines for obstructions or kinks.
4. Verify that the sensor wiring is correct and secure. “Wiring the Sample-Draw Detector to a
Controller” on page 10 describes sensor wiring connections.
5. Calibrate the sample-draw detector as described in “Calibration, LEL Sensor” on page 19 and
“Calibration, Oxygen Sensor” on page 21.
6. If the fail condition continues, replace the sensor(s) as described in “Replacing Components of
the Sample-Draw Detector” on page 16.
7. If the fail condition continues, contact RKI Instruments, Inc. for further instruction.
Slow or No Response/Difficult or Unable to Calibrate
Symptoms
•
The sensor responds slowly or does not respond during the monthly response test.
•
Unable to accurately set the zero or response reading during the calibration procedure.
•
The sensor requires frequent calibration.
Probable causes
•
The calibration cylinder is low, out-dated, or defective.
•
The fixed flow regulator is not functioning properly.
•
The sample-draw detector’s flow rate is too low because of an obstructed sample line, failed
pump, etc.
•
The dilution fitting is blocked.
•
The sample-draw detector is malfunctioning.
Recommended action
1. Verify that the calibration cylinder contains an adequate supply of a fresh test sample.
2. Use a different fixed flow regulator to determine if the original one is functioning properly.
3. If necessary, set the correct flow rate with the sensor flow control valve.
4. If you cannot set the correct flow rate, check the sample line for obstructions or kinks.
5. Check the dilution fitting for obstructions.
6. If the calibration/response difficulties continue, replace the sensor as described later in this
section.
7. If the calibration/response difficulties continue, contact RKI Instruments, Inc. for further
instruction.
