Possible cause

Solution

Restriction in the system plumbing

Procedure

  1. Check all liquid lines for crimping or blockage. Make sure the ferrule fittings are not overtightened onto tubing. For details, see Replace tubing and fittings.
  2. If you have trouble isolating the restriction, see Isolate a restriction in the tubing.

Plugged or damaged fitting

To isolate the faulty fitting, loosen each fitting until the pressure returns to normal. Repair or replace the fitting (see Replace tubing and fittings).

Flow rate through the columns too high

Set the correct flow rate for your application.

Clogged column bed supports

Refer to the instructions in the column manual for troubleshooting guidance.

Contaminated columns

Clean the columns as instructed in the column manual or replace the guard column.

Plugged injection valve or auxiliary valve passages

Rebuild the valve (see Rebuild the injection valve or auxiliary valve).