Preferred FlexFit 110 - Low Calibration Gas Flow Rate; Detector Leak Test

5-90 Troubleshooting – ZP Oxygen Analyzer Troubleshooting
FlexFit – Linkageless Control – Revision 1.0
PREFERRED
UTILITIES MFG CORPORATION
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Low Calibration Gas Flow Rate
Disconnect the tubing at the calibration port on the detector. Verify that the gas is owing up to the detector. If the detector
ange is overheated, the elastomer calibration gas check valve may become stuck shut. Use a toothpick or paper clip to gently push
open the check valve.
Figure 5 – 1
Filter
Temperature Label
Calibration Port
Check Valve Inside
Viton Seal Inside
Calibration Port Check Valve
Detector Leak Test
If the cell is cracked or broken, ue gas can leak into the reference side of the cell and cause an incorrect reading. If the Viton
seal between the cell tube extension and the detector head is overheated it can leak and cause an incorrect reading. See "Measuring
Principle" on page 2-30, for the principle of operation.
Test for Leaks as follows:
1. Turn off the power and remove the detector from the process. Wait for the detector to cool down. Remove the outer lter
and the inner calibration gas deector washer.
2. Insert a small paper clip or toothpick into the check valve, to hold it open during the test (remove after testing). Using a
rubber sheet or the palm of your hand to seal the end of the threaded tube, pressurize the calibration port to 10-15" H
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The detector should hold pressure. If the pressure drops, replace the detector.
All detectors are inspected and pressure tested before shipment. The reason for the broken cell could be:
• Dropped during shipping, receiving, or installation.
• Hit with liquid water when hot.