All About Irrigation Master Valves
This article explains what an irrigation master valve is. Sprinkler Warehouse has also provided a diagram of how to wire a master valve to an irrigation system.
A master valve is an electric valve installed at the supply point which controls water flow into the main piping system. When this valve is closed water will not be supplied to the irrigation system.
Reducing Your Water Loss
A master valve will greatly reduce any water loss due to a leaky station valve. This is because the leaky station valve can only leak while the master valve is providing pressure to the system. Also, if you damage the irrigation mainline, a master valve will control water loss. It does this so that the main can be repaired without shutting off the water supply.
Where To Install A Master Valve
A master electric valve is typically the same type that you would use for your station valves. However, rather than being installed downstream from your mainline and connected to a station output in your controller it is installed upstream at the front of the mainline. Then it is connected to the “master” or “pump” connection in your controller. Not all controllers support a mater valve or pump- be sure to check the features before buying a controller.