How often should I change the filter elements on my hydraulic system?

How often should I change the filter elements on my hydraulic system?

Many filter housing have an indicator which shifts from Green to Red when it is time to change the filter element. Sometime this is a needle pointing to a red or green area of a gage, other times it is a pop-up button which changes color.
While waiting for the indicator is effective, many machine operators prefer to change in time. The most used change out interval is 6 months, and the interval should never longer than one year. Even with an indicator, every element should be changed out at least once a year. Fluid sampling and laboratory analysis is also important. But this is more to monitor the equilibrium cleanliness level of the fluid. Waiting until the laboratory report shows elevated contamination levels is not advisable, as the hydraulic components would run on dirty fluid until the higher levels are detected, and the elements changed. Remember filter elements are always less expensive than damaged components.