If the Lachat flow cell (Catalog Number/Order Code 31933) is leaking does it need to be replaced?
How to resolve Lachat flow cell leaks.
The issue is not with the cell itself. Flow cell leaking relates to how well the tubing flares seal against the interior of the flow cell. In this case, it will not leak from the fittings, it will leak from the seam around the glass. Try tightening the fittings if this has not been done already. For union, tee and PTA connections, be careful not to over tighten or the o-rings can crimp the tubing. For the flow cell connection, tighten the fittings more so than for the other o-ring connections. Also, make sure to use three o-rings (unlike the other connections which only use two). Typically, a flow-cell leak can be resolved by tightening the fittings or replacing the flares (Catalog Number/Order Code 50065 and 50067) and o-rings (Catalog Number/Order Code 50013). With good lighting, one can also look into the flow cell after removing the flares. A nice flat surface should be seen for the flare to seal against. Sometimes salt deposits from precipitated reagent may be present. If this is the case, try cleaning the surface with a cotton swab and water or isopropanol. Once a leaking flow cell is discovered, make sure to remove and clean the detector's fiber optic cables.