Why does my front-loading valve leak out the injection port only while I am in the LOAD position loading the sample loop?
If the needle seal located in the rotor seal is not sealing around the needle, some of the sample will come out of the injection port. The outer diameter and length of the needle must be the correct size for the valve in order for the needle seal to function. If the OD and needle length are correct, the needle seal may have expanded through frequent use. The needle seal can be reformed by pushing down on the needle guide, which in turn pushes on the seal and closes it up. For more information see Tech Tip 3: How to Find and Fix Common Leaks. Note: Never use a beveled, pointed, or tapered needle. This can permanently damage the rotor seal and stator face assembly.
