How to install a water softener drain

Written by robert sylvus
  • Share
  • Tweet
  • Share
  • Email

A water softener's drain must not connect directly to a home's drainage system without an air gap between the end of the water softener's drain line and the home's drain system. The air gap eliminates the possibility that a negative pressure in the water softener will suck sewer water into the softener's storage tank. If a break occurred in the water-supply pipes, the negative pressure created from the water flowing out of the softener's tank pulls whatever the drain line connects to into the tank. Water softeners need a drain line installed for the tank's routine maintenance.

Skill level:
Moderately Easy

Things you need

  • Adjustable wrench
  • Pipe thread compound
  • Plumber's tape
  • 1/2-inch braided drain tube
  • Knife
  • Pipe hangers
  • Drywall or concrete screws
  • Electric drill

Show MoreHide


  1. 1

    Remove the water softener's 3/4-inch drain plug, usually located near the water intake pipe. Turn the plug counterclockwise with an adjustable wrench until it spins freely, then spin the plug with a hand.

  2. 2

    Cover the water-softener drain fitting's last three threads with a pipe thread compound or plumber's tape. A water softener's drain fitting has threads on its 3/4-inch side and ribs on its 1/2-inch side.

  3. 3

    Position the drain fitting's threads against the water softener's drain hole and twist the fitting clockwise. Hand tighten the drain fitting.

  4. 4

    Twist the drain fitting one full turn clockwise with the adjustable wrench. Do not over tighten the fitting.

  5. 5

    Locate a suitable code-approved drain opening, using local building codes as a guide. Many water softeners dump waste water into a clothes-washing machine's drain pipe, while other water softeners use a floor drain. Some homes are pre-plumbed for a water softener and use a 1/2-inch pipe penetrating the wall near the floor as a water softener drain connection.

  6. 6

    Push the end of a 1/2-inch braided drain tube onto the water softener's drain fitting. Push the end of the tube onto the 1/2-inch end of the drain fitting until it passes the ribs and butts against the back of the 3/4-inch side of the fitting. The rib locks the tube in place.

  7. 7

    Run the tube to the suitable drain opening and cut the tube to size with a knife. If the end of the tube slips into a clothes-washing machine's drain, extend the drain 8 to 12 inches down the drain opening. If the tube connects to a pre-plumbed drain pipe, force the end of the tube over the drain pipe's fitting until it passes the pipe fitting's ribs. If the water softener's drain tube dumps into a floor drain, run the tube to the floor drain.

  8. 8

    Secure the water softener's drain tube with pipe hangers. Mount the pipe hangers to the wall or floor every 2 to 4 feet with screws. The type of screw depends on the wall or floor's material. Generally, drywall screws work on walls and wood floors. Concrete or tile floors need a pilot hole drilled and a concrete screw installed. Concrete screws come packaged in a kit with the appropriate size drill bit. Drill the pilot hole with an electric drill equipped with the drill bit supplied with the concrete screw kit.

Don't Miss

  • All types
  • Articles
  • Slideshows
  • Videos
  • Most relevant
  • Most popular
  • Most recent

No articles available

No slideshows available

No videos available

By using the site, you consent to the use of cookies. For more information, please see our Cookie policy.