Does the Water Filter Go Before the Pressure Switch?

About Water Pressure Regulators

• Water pressure regulators are installed in almost every home. These bell-shaped valves regulate the amount of water pressure that enters the house plumbing system from the main water connection to the well or street lines. Water pressure regulators are typically installed very near where the water enters your home, usually inside a basement or crawl space. The regulator may also be installed inside a plumbing access panel or outside utility shed, if the water line runs to an outdoor irrigation system prior to entering the house.

About Water Filters

• Water filters are available in several configurations. Faucet filters attach directly to the aerator attachment on the end of kitchen faucets. Other filters are installed in refrigerator water dispensers or on pipes that service specific fixtures inside the house. Whole-house water filters are installed on the main water pipe that services the entire home. Most filters require only compression fittings for installation, making them relatively simple to install with limited knowledge about plumbing fitting and techniques.

Water Filter Placement

• The only type of water filter that requires special consideration when choosing an installation location is the whole-house filter. These devices are large and clean water before it enters the main plumbing system. But these filters should never be installed before the water pressure regulator, as the large amount of pressure from the street or well connection may damage the filter medium. Instead, whole-house filters should be installed at least 3 feet after the regulator. This will ensure that the water pressure is reduced enough so that it will not damage the filter.

Addressing Pressure Problems

• Although a whole-house water filter should be installed after the water pressure is reduced, you may still adjust the pressure levels to optimize shower heads and other fixtures. Adjust the water pressure by loosening the nut on the pressure regulator and turning the adjustment screw clockwise. The further you turn the screw, the more water pressure will be allowed to enter the plumbing system. Most filters will have a pressure limit listed on the box or side of the filter itself. Do not set the regulator beyond this limit.