Flow restriction or blockage from detector cell or backpressure coils should be eliminated first to avoid irreversible damage to the suppressor.

Troubleshooting tasks

Task

Procedure

Backflush the detector cell

Procedure

  1. Bypass the suppressor and connect the column outlet tubing to the detector cell outlet port and direct the detector cell inlet tubing to waste.
  2. Turn on the pump and flow eluent at the application flow rate for 10 minutes. Turn off the pump. Re-measure the detector cell backpressure by following the steps in Hydration.

NOTE: Repeat the backflush procedure if the backpressure remains high. If the backpressure of the detector cell doesn’t come below 70 psi after multiple attempts, replace the detector cell.

Adjust backpressure coil

Procedure

  1. Do one of the following:
  2. If the pressure is greater than 40 psi for carbonate eluent or other eluents, trim the backpressure coil and repeat the backpressure coil test in Hydration.
  3. If it is less than 30 psi for carbonate eluent or less than 10 psi other eluents, add more tubing and repeat the backpressure coil test in Hydration.

NOTE: Backpressure coils help to prevent gases generated during AutoSuppression from out-gassing by compressing the bubbles. The bubbles can be occasionally trapped in the detector cell causing noise. For example, carbonate eluent is suppressed to carbonic acid, which is CO2 gas in equilibrium with DI water, and CO2 gas can come out of solution if adequate pressure is not applied. Therefore, we highly recommend the addition of 30-40 psi for carbonate eluent or 10-40 psi for other eluents.

Backflush suppressor with DI water

Procedure

  1. Turn off the pump and disconnect the column outlet and cell inlet tubing from the suppressor eluent ports (if not already disconnected).
  2. Connect the DI water tubing from the pump outlet directly to the suppressor eluent out port and direct the eluent in tubing to waste. (Effectively plumbing the eluent ports backwards to reverse flow through the eluent chamber).
  3. Turn on the pump and flow DI water at 1.0 mL/min for 4 mm suppressor and 0.25 mL/min for 2 mm suppressor for 10 minutes. Turn off the pump. Re-measure the suppressor backpressure by following the steps in Hydration.

NOTE: Repeat the backflush procedure if the backpressure remains high. If the backpressure of the suppressor doesn’t come below 200 psi after multiple attempts, replace the suppressor or contact your Service Engineer or Technical Support team.