Generally speaking, they can be installed in Suction, Pressure, Return and Re-circulating lines. Mioronic Suction Filters are not recommended for open-loop circuits. The cavitation these filters can cause far outweights any advantage obtained by attempting to clean the fluid in this part of the system. Large sized housings are required in order to keep the pressure drop low. As a consequence, this means a relatively higher cost to the user.
Most engineers use a coarse suction strainer to capture large particles.
Pressure Filters protect downstream components from pump wear and generally produces the lowest contamination level in the system. However, the housing is relatively expensive because of the requirement to tolerate full system pressure. Return Line Filters are most often considered when initial cost is a major concern. Also, a significant concern in applying return line filters is sizing for flow. Long and frequent flow surges are detrimental to the use of return line filters.