Boiler valves are available for purchase at Grainger and Home Depot, as of 2015. Both stores have boiler drain valves in a variety of sizes and colors and at different price points. Grainger also has boiler feed valves available.
Boiler drain valves are useful for keeping water drained in a boiler and getting rid of dirt that may have settled. These valves also function as a hose connection for an outdoor water service or as a connection between a laundry tub and washing machine. However, the valves should not be used to procure drinking water. Most boiler drain valves are constructed of brass.