Lawn Sprinkler Guide to Winterization.

Freezing temperatures aren’t here yet, BUT they are right around the corner here in NJ.

Winterizing your lawn sprinkler system (removing the water from the piping, valves and sprinkler heads) is essential prior to any freezing occurring. It is the BEST way to potentially protect from serious damage this Winter. There are 3 techniques :

  1. The manual drain method
  2. The automatic drain method
  3. The compressed air blow-out method (most widely used in NJ)

Always use extreme care when blowing out the system, Excessive pressure can damage valves or sprinkler pipe. There is also the risk of injury from flying debris. Never stand directly over the sprinkler pipe, valves or heads during this process.

The compressed air blow-out method uses compressed air to clear any water from the lawn sprinkler pipe, valves and heads. Most Lawn Sprinkler Companies offer this service at a reasonable rate. Depending on the size , design and type of equipment used in your system, it probably would be beneficial to choose a professional whom is fully equipped, licensed and trained to provide this service.

If you plan on winterizing your own lawn sprinkler, make sure to use the right air compressor for the job. It is not recommended for the PSI to be more than 50psi. Small shop compressors (2hp) are not adequate for the job.


Your lawn sprinkler system should have been designed offering a quick disconnect fitting, plugged “tee” or capped pipe in the line specially used for air hose. This connection should be located as close to the water source as possible. Usually near the PVB.

After draining the lawn sprinkler system, the controller needs to be protected also from the Winter.

  • If you have a Programming dial on your controller – Turn the dial to the “OFF” position. You can choose to keep plugged in over the Winter to maintain the programming (if there is battery back-up) or unplug to reduce risk of power surge incidents.
  • If you have a DIGITAL controller (EZ-1,  CRC or ISC models from Rainbird)- Turn system to “SYSTEM/OFF” or “AUTO/OFF”. Now the common wires need to be disconnected from the valves and/or pump relay. You may opt to unplug the controller to protect against possible power surges. Finally disconnect the wire or wires marked “COMMON or COM” remembering to place either a wire nut or electrical tape over any loose wire ends.

If you have a Backflow Preventor (PVB) valve (required in the state of NJ) the manufacturers recommend:

  • Leaving shut-off valves open after unit has been drained. Also the plug is usually left loose. Under extreme conditions insulate the device or use heat tape to prevent damage.  Most professional lawn sprinkler technicians will have “dis-assembled” the PVB as explained above, which will need to be re-assembled in the Spring.

Although it is highly recommended to call a professional to winterize the lawn sprinkler, a lot of homeowners are preferring to perform this themselves. As always be careful, be aware of proper procedure when performing a winterization and make sure to follow any manufacturer’s instructions.

Taking the time to fully winterize all components of your lawn sprinkler system will help in protecting the system over the Winter, it will also extend the life of the components in your lawn sprinkler system for many seasons to come.