Browse a selection of isolation valves from F.W. Webb and find the right products for your tankless water heater. These valves are essential when performing routine internal maintenance. An isolation valve allows access to cold water when disconnecting a tankless heater from the plumbing system while you drain and flush it. We offer isolation valves and kits in an assortment of sizes, materials, and end connections so you can find the right product for your plumbing needs. Explore tankless water heater isolation valves and kits from trusted brands including, Webstone, Red White, Navien, and NTI Boilers.