DIRECTIONS FOR DRAINING THE BACKFLOW PREVENTER OF A LAWN SPRINKLER SYSTEM
COLD WEATHER PROCEDURE (anytime air temperature is below 32 degrees)
STEP 1 In your basement, close the shut-off valve on the pipe to your lawn sprinkler
system.
STEP 2 Also in your basement, open the drain on the pipe to your lawn sprinkler system.
Some water will drain out as this 5 step procedure continues, so you might want
to put a bucket or pail under the drain to catch the water.
STEP 3 Outside your house, open the test valves on the backflow preventer by turning the
slotted screws (either clockwise or counter-clockwise) ΒΌ turn or 90 degrees. As you can see,
whenever the slot is parallel to the body of the test valve, the valve is open. Opening the
test valves allow pressure inside the backflow preventer to be released.
STEP 4 Turn the isolation ball valves on the backflow preventer to a 45 degree position.
Do not turn the handles so that they are perpendicular (90 degrees) to the ball valve.
STEP 5 Go to the lawn sprinkler controller and start a cycle. This will help drain the pipes
exposed to air. (Obviously, the sprinkler heads will not pop up as usual because
the water supply remains shut-off). Operating the controller in this manner will
not harm the sprinkler system.