Exchanging the Purge Valve Frit or the Purge Valve

When

Frit – when piston seals are exchanged or when contaminated or blocked (pressure drop of > 10 bar in low delay volume configuration and > 20 bar in standard configuration across the frit at a flow rate of 5 mL/min of water with purge valve opened)
Purge valve – if internally leaking

Tools required

Parts required

Prerequisites

Switch off pump at the main power switch
Open the doors
Use an optional solvent shutoff valve or lift up solvent filters in solvent reservoirs for avoiding leakages

Using a 1/4 inch wrench disconnect the pump outlet capillary from the purge valve. Disconnect the waste tube. Beware of leaking solvents due to hydrostatic pressure.
Using the 14 mm wrench, unscrew the purge valve and remove it from the purge valve holder.
Remove the seal cap from the purge valve. Using a pair of tweezers or a toothpick, remove the frit.
Place a new frit into the purge valve with the orientation of the frit as shown below (slit in frit points to the front). Reinstall the seal cap including the gold seal.
Insert the purge valve into the purge valve holder.
Tighten the purge valve and reconnect outlet capillary and waste tubing.

21-Jun-2025