Zone valves are an important component of many HVAC systems, and are used to control the flow of heated or cooled air to specific areas of a building. They are usually connected to a thermostat, and are activated when the temperature in the area reaches a certain level. Zone valves can be manual or automatic, and can be used to control the temperature in one or more zones. They are typically installed in the ductwork of a building, and are used to control the flow of air to specific areas. Zone valves are also used to regulate the temperature of water in a hot water heating system, and can be used to control the flow of hot water to different areas of a building. Zone valves are an important part of any HVAC system, and can help to ensure that the temperature in a building is kept at a comfortable level.