Maintenance – RKI Instruments 35-3000RK-LEL/O User Manual

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35-3000RK-LEL/O Sample-Draw Detector • 11

for the oxygen channel, continue with step 3.

Perform a zero operation at the controller. See the controller operator’s manual for
instructions to perform a zero operation.

Maintenance

This section describes maintenance procedures. It includes preventive maintenance
procedures. This section also includes procedures to troubleshoot the sample-draw
detector, replace components of the sample-draw detector, and adjust the low flow
setting.

Preventive Maintenance

This section describes a preventive maintenance schedule to ensure the optimum
performance of the sample-draw detector. It includes daily, monthly, and quarterly
procedures.

Monthly Visual Checks

Verify that the pilot light is on.

Verify that the flowmeter indicates a flow rate of approximately 1.5 SCFH.
If necessary use the bypass valve or flow adjust potentiometer to adjust the flow rate
to 1.5 SCFH.

Verify a display reading of 0 %LEL for the combustible channel and 20.9% for the
oxygen channel at the controller. Investigate significant changes in the display
reading.

Monthly Response Test

This procedure describes a test to verify that the sample-draw detector responds properly
to the target gas.

NOTE:

To reduce the response time of this test, use a short incoming sample line. If the
sample-draw detector’s sample line is long, connect a shorter line for this test.
Make sure you reconnect the sample line after you complete this procedure.

NOTE:

Performing a response test on the sample-draw detector may cause alarms. Be
sure to put the controller into its calibration program or disable external alarms
before performing this test.

Preparing for the response test

NOTE:

This procedure describes the RKI calibration kit that includes a demand flow
regulator.

Verify that the display reading at the controller is 0 % LEL for the combustible channel
and 20.9% for the oxygen channel.

If the display reading is not 0 % LEL for the combustible channel or 20.9% for the
oxygen channel, set the zero reading as described in the Calibration section, then
continue this procedure.