#AIR ADMITTANCE VALVE REVIEWS 2017 CODE#

It must be located a minimum of 4” above the horizontal branch drain, 6” above any insulation material and within 15 degrees of vertical. AAV locationĪn AAV should be located within the maximum developed length permitted for the vent. In other words, AAVs with PVC adapters should only be paired with PVC pipe, and AAVs with ABS adapters with ABS pipe. Generally, a vent should be sized to be half the pipe diameter of the drain it is serving (refer to local codes for specific vent size recommendations).Īdditionally, you should verify what type of pipe material you will be connecting the AAV adapter to ensure compatibility. The adapter size is based on the diameter of the vent pipe it is being installed on.

Proper AAV sizing is critical because under-sizing will not allow the plumbing system to operate properly.ĪAVs are typically available with 1 ½”, 2”, 3” and 4” adapter connections. To ensure proper breathing capability, determine all fixtures to be vented and calculate the total DFU load, then select the appropriate AAV for the application. Common fixture load ratings are shown in the table below. The higher the DFU rating on the valve, the greater amount of air that can enter the Drain-Waste-Vent (DWV) system.ĭFU loads are assigned to plumbing fixtures dependent on the volume rate of discharge, the duration of operation and the time between operations. An AAV’s ability to breathe is measured in DFUs.

You can determine which size AAV you’ll need based on the Drainage Fixture Unit (DFU) load of the fixture(s), such as an island sink or bathroom group, it will vent. If the use of an AAV is not permitted, the fixture or drainage system will have to be vented traditionally through the home’s existing venting system.

#AIR ADMITTANCE VALVE REVIEWS 2017 CODE#

Key Considerations Local Code and Manufacturer Requirementsīefore heading to your local hardware store, be sure to check with local municipality codes and manufacturer requirements to determine if an AAV is approved for your particular application.

Air admittance valve reviews 2017