Abstract: Currently, there are no products available which allow a user to solely remove microbial and bacterial growth inside a blocked HVAC condensate drain line using compressed air without cutting into or disassembling the drain line. Our valve is an in-line condensate drain line valve that can be installed easily, quickly and economically, either during new construction or onto existing HVAC systems. The HVAC user can remove microbial and bacterial growths without cutting into or disassembling the drain line by injecting compressed air through the valve. The design of our valve allows the user to perform safe and routine maintenance to the HVAC drainage system without having to resort to expensive and repetitive service call repairs over the lifetime of the HVAC system. The valve is further designed to prevent undesirable reverse airflows into the HVAC system and home or building, caused by a dry trap in the condensate drain.