Homeowners will need to drain their sprinkler systems in preparation for winter weather, or to make repairs to the system. Based on the type of drain the installers added to a system, you have a couple of options for draining the lines. Prior to starting, determine which type of drain valves you’ve got on your sprinkler system. You may check the directions which came with your irrigation equipment or call the installers. Use either automatic or manual drain valves, based upon your installation. A third option, which uses compressed air to drive water in the lines, which is best left to a specialist.
Manual Drain Valve
Locate the manual drain valves located downstream of each zone valve. These are the ones in the lowest points in the sprinkler system, which is where water accumulates when the system is closed off.
Switch off the water supply by closing the main valve to the sprinkler system. These vales are often located on another division near the water meter. Look for a “T” connection.
Open all the manual drain valves for each zone in the system, and leave them open to ensure that all of the water drains in the pipes and sprinkler heads. Leave them open for a few days, if at all possible.
Open drain valves found upstream of each zone valve to dump water from the primary line.
Lift each sprinkler head to drain out any residual water left inside.
Close all of the drain valves.
Automatic Drain Valves
Switch off the water supply by closing the main valve to the sprinkler system. As pressure inside the system falls, it is going to drain water automatically.
Open the drain cap involving the primary valve and the backflow device. This removes any water trapped within this section of piping.
Lift each sprinkler head to drain out any residual water.
