NO/NOx analyzer pressure control / bypass flow problems

The designer of this analyzer failed on two major points:

  1. He specified all sample tubing to be 1/8″ OD.  This is OK for some parts of the internal gas handling system but not for all parts of the sample tubing.
  2. He did not include a flow restrictor at the sample inlet.

Discussion (later)

Fix / upgrade / resolution:

  1. Change the reaction chamber exhaust tubing to 1/4″ OD Versillon or Tygon or Neoprene tubing.  Also change the BPR exhaust lines to 1/4″ OD tubing.
  2. Install a special, modified (with embedded restrictor), adapter at the sample inlet (4-4 TRBZ-SS or 2-4 TRBZ-SS) at the inlet (it attaches directly to the OEM’s SAMPLE INLET port).  RIGAS makes these on demand.