does an air admittance valve go before or after a trap

does an air admittance valve go before or after a trap. There are some references to does an air admittance valve go before or after a trap in this article. If you are looking for does an air admittance valve go before or after a trap you've came to the right place. We have posts about does an air admittance valve go before or after a trap. You can check it out below.