Winterization of Lawn Sprinkler Systems
Winterization of lawn sprinkler systems is necessary in cold climate areas where ice can cause damage to sprinklers, valves, piping, backflow preventers and other system components. Even if you have drained the system with a Manual Valve Method or Automatic Drain Valves, it is possible that some water may remain in valves and sprinklers. Therefore, the “blow-out” method using compressed air is generally recommended.
Weathermatic recommends that you utilize a qualified service contractor to winterize your system. Use of compressed air can damage sprinkler system components if the “blow out” is not done following recommended safety procedures. If you do not have a service company that you use, we recommend that you go visit our Find a Distributor Page to find a local distributor. The local
distributor can recommend qualified service companies specializing in winterization.
Weathermatic recommends that you ask your service company for an annual
winterization and spring turn on contract. It is important that the contract include the spring check up as well as winterization. That way, your service company can spot any problems that occurred at blow out or over the winter months and correct those for you at the beginning of the season.
Compressed Air Winterization Information
Blow out air pressure should never exceed 75 psi for PVC pipe or 50 psi for
polyethylene pipe. Volume must be 50 to 125 CFM. It should never be lower than 50 CFM. Pressures exceeding 75 psi can cause air pockets to develop in the upper chamber of the valve.
Weathermatic recommends that during the winter months your system controller be kept running during the winter months as this helps to keep the electronic components active and fresh. It is also important that older electro-mechanical controllers be left plugged in so that the gears, bushings and bearings do not take a set over the winter months. HOWEVER, THE CONTROLLER MUST BE SET IN THE “SYSTEM OFF” POSITION TO PREVENT THE CONTROLLER FROM TRYING TO ACTIVATE VALVES DURING THE WINTER MONTHS. YOUR SERVICE CONTRACTOR WILL TURN OFF THE MASTER MANUAL CUTOFF VALVE AT THE TIME OF WINTERIZATION.
If you are located in a moderate climate with occasional freezes, blow out is normally not required. However, you may need to wrap your backflow preventer. Water standing in above ground riser pipes can also be a problem. However, if a pop up lawn head is on the same zone with a riser zone or if the zone has an automatic drain valve, then the water in the riser pipe will drain out during normal operation. Check with your local service company for recommended winterization for your system.