How Valco Filters Differ from Valco Unions

Filters with removable frits are designed to compensate for the thickness of the filter element - the resulting pilot depths are identical with the rest of the Valco product line, facilitating interchangeability of made up fittings. Therefore, although our filters look very much like our unions, they are not interchangeable with unions; a filter with its frit removed should not be substituted for a union, because the space designed for the frit introduces dead volume into the system.

In addition, since filter bodies are coned, they will have dead volume when used as a union even if the tubing is made up in the filter with a longer, non-standard pilot length.