Installing an air valve

Install an air valve

An air valve, also known as an air admittance valve, is a one-way mechanical vent that is mostly used to be put in a plumbing system so as to help eliminate the need for a conventional pipe venting and roof penetrations. Air valves are used to basically allow air to get in the plumbing vent pipe for a better drainage. Other than that, the air valve just stays close thus preventing the release of sewer gas and helping to maintain the trap seal.

If there is an emergency for you to install an air valve or AVV to add the pipe ventilation, it is useful to have experience in plumbing and the ability of shutting down the main water valve. You should also check with the local code authority to verify whether they accept the use of air valve that you are going to use before installing it. You could purchase complete kits of bigger or smaller air valve at plumbing stores and online retailers. Smaller valves are designed to service only one unit at a time while larger valves can support more than one unit of sink or shower. For toilets, it is better vented outside via a stack vent in the roof. This will prevent airborne disease and odor problems from collecting inside the bathroom. Here are the steps on how to install an air valve.

You will need:

  1. Air admittance valve
  2. Plumber\’s tape or pipefitting adhesive
  3. Old clean towels
  4. Pipe wrench
  5. Flashlight
  6. Tools that are needed based to your air valve kit\’s instructions


  1. First, make sure that all of the required tools are ready and are placed nearby you before starting your installation. A flashlight will become handy if the work area is dark. If you have an extra space while working, ask a partner to hold the flashlight for you instead. Mop any drips and keep the floor clean by using the old towels.
  2. Then, turn off the water flow to the unit. The air valve should be placed in an area that allows free air flow as well as good physical access. Often, they are fitted to the drain line which is between the trap and the wall. The highest part of the trap where it turns lateral is usually four to six inches above the weer. You can purchase adapter pieces to fit the pipe size if necessary. Use a suitable sealing tape or chemical welding material to secure it tightly in place.
  3. Test your air valve once it been installed. Turn the water back on and then turn the water on in the sink or shower or try flushing the toilet. If there are no unusual or strange noises or actions after several tests, then the air valve is installed properly and venting the air as it should.

To have an air valve installed allows for a greater flexibility when it comes to the layout of plumbing fixtures. It helps to reduce long-term maintenance problems that are usually associated with the usual vent stack roofing penetrations.

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