Taco valves are used to control the flow of water, steam, or other fluids in heating, cooling, and other systems.Taco is a company that manufactures and distributes a wide range of valves for HVAC and plumbing systems. Some of the types of valves that Taco offers include: Zone valves: These valves are used to control the flow of water or steam in individual zones or rooms in a buildin... https://www.partshnc.com/m/taco/taco-valves