1. Clamp the column, with outlet and inlet plugs in place, in a ring stand or a bench vice with the column inlet pointing up.
2. Allow the column to equilibrate to room temperature before removing the column end fitting.
3. Carefully loosen and remove the column end fitting. Hold the column end fitting steady with one wrench while loosening the column nut with another wrench until it drops away from the end fitting.
4. Remove the column distributor frit using a frit removal tool or by pulling up on the plastic housing. Be careful when removing the frit to prevent the loss of significant gel from the tube end.
5. Clean the top surface of the column by gently scraping a flat spatula or a razor blade across the gel surface. Be sure to avoid disturbing the packing material in the column. To get the surface even you may have to wet the packing with whatever solvent is in the column or another miscible solvent.
6. Place a new distributor frit cap on top of the cleaned surface of the column. Press the frit firmly down onto the column end.
7. Rinse all residual packing material from the column end fitting and frit. Failure to remove packing material from threads and sealing surfaces, e.g. frit may result in leaks or clogging.
8. Replace the column end fitting. Use wrenches to tighten the end fitting nut approximately 1/4 turn past finger tight. Do not over tighten.
9. Connect the column to the chromatograph and check for leaks.
10. If the column leaks, turn the pump flow off, allow the pressure to bleed off, and then tighten the end fitting nut slightly more, approximately 1/8 of a turn.
