Clean and Verify the Gas Line

Always clean the gas lines and verify there are no leaks at the connections after a gas cylinder is connected. This test examines the gas line from the analyzer to the gas cylinder, then from the analyzer to the regulator shutoff valve. A report is generated at the completion of the test to verify that it has passed or failed. Causes and corrective action for a failure are provided.

Before beginning, confirm that the state for valves and the low pressure gauge are as follows:

  1. Gas tubing to instrument
  2. Gas regulator shut-off valve - OPEN
  3. Low pressure gauge - 14-15 psig
  4. High pressure gauge
  5. Gas cylinder shut-off valve - CLOSED
  6. Regulator connecter nut
  7. Regulator control knob - OPEN
  8. Brass reducer fitting

  1. Select Clean and Verify Analysis Gas Line [n] Test Rev [n] in the Test field. The length of time a test will run is also indicated on the window. The Sequence field indicates the file created as a result of this test.
  2. In the Operator field, enter either the name or initials of the operator performing this test.
  3. Resize the window (if necessary) to display the Report after test option, then select Preview as the destination. Click Start.
  4. From the View drop-down list, select either Operation, Instrument Log, or Instrument Schematic.
  5. The following series of prompts display on the window requiring operator response:
  1. This is the gas line clean and leak check test for inlet port [n]. Inlet ports being tested must be connected to a gas cylinder according to the user manual. A Nupro isolation valve should be installed on the line between the analyzer and the regulator.
  2. The test starts with a manual leak check (requires Snoop or equivalent, and IPA), then the line and regulator are evacuated for 20 minutes for cleaning. Next, the leak rate of the gas line is determined.
  3. With the regulator set to 15 psig, open the cylinder, regulator shutoff valve, and isolation valve. Check each joint for bubbles with Snoop or equivalent. If a joint is leaking, attempt tightening (without over-tightening) or replace ferrules.
  4. When there are no leaking joints, use IPA to remove water from each joint, then wipe dry.
  5. Close the gas cylinder valve. Leave the regulator shutoff and isolation valves open.
  6. User will be needed in 30 minutes to close the isolation valve. Click OK to begin automated testing.
  1. A popup window indicates the test is complete. Click OK. The reports display.

  1. Click each tab across the top of the window and look for a reading of Passed. A Passed reading indicates all valves are in a proper state for operation. If any test shows a Failed reading, refer to the following table to help determine the location of the gas leak.
Tab Test If Failed status, then...
Gas Line to Inlet Port [n]
Test 1
Gas Line to Gas Bottle Test This test will show a reading of Failed if any of the other tabs has a Failed reading. Correct the failed connection and rerun the test.
Gas Line to Inlet Port [n]
Test 2
Gas Line to Isolation Valve Test Check for a leak between the gas line and the isolation valve. Correct the problem and rerun the test.
Gas Line to Inlet Port [n]
Test 3
Isolation Valve To Bottle Leak Rate Check for a leak between the isolation valve and the gas cylinder. Correct the problem and rerun the test.

If the Fail if above field indicates Failed, one or more valves is not in the proper position. Set the valves, then ensure the appropriate pressure is displayed on the low pressure gauge.

If re-running the test, close the gas cylinder valve before starting the test.