Yes Pre-filter can effectively filter out the secondary pollutants in tap water, such as sediment, rust, particles, floating objects, microorganisms, etc., and then enter the room; Secondly, due to the filtering function of the pre-filter screen, the damage of the above pollutants to the water purifier, water heater and shower at home can be avoided, thus prolonging the service life of the above appliances. Therefore, the filtering function of the pre-filter is of great benefit to health and household equipment, and it is still worth installing. Precautions for pre-filter should be installed indoors at room temperature not lower than 0℃, because the volume of water will expand during solidification. If it freezes, the pipeline and filter bottle of pre-filter will burst directly, causing water leakage. If installed outdoors, anti-freezing measures must be taken. If there are no anti-freezing measures, the pre-filter may freeze and crack, and the pre-filter must be stopped when the temperature is below zero. If you don't use the front filter for a long time or need to go out, be sure to close the water inlet ball valve, drain all the water from the filter bottle, and check whether the machine looks normal before using it.