Are the spray or rotary heads on your lawn sprinkler system constantly sticking up when they ought to be retracting into the grass?
Don’t worry, this is all too common and is probably caused by a couple of things.
Q. How old are your sprinkler heads?
A. From years 3 and beyond, the wear & tear on the riser fittings will cause rough edges which then cause the head to stick up.
Q. Is your soil sandy?
A. If you answered yes, the risers will wear even faster.
The only way to resolve this is to replace the damaged sprinkler head.
To prevent this, there are a couple of things you can do. You can have the sprinkler heads either replaced with stainless steel heads and risers (which will cost much more) or in some instances you can carefully step down on the sprinkler head while the system is running, let it pop back up and then step down on it again. Do this a few times and see if the head is still sticking.
If there are more than 1 or 2 heads with this issue, I would recommend flushing the sprinkler system. This can be done by removing all the sprinkler nozzles and screens on the heads and installing flush caps, then running water through the sprinkler system. You could also do this by removing the sprinkler head completely, pulling up the swing joint and then flushing. Rotary heads must be flushed in this manner anyway.
If your sprinkler system is older and your heads are not installed on swing joints just make sure you dig around the riser that the head is attached to, making sure that no dirt can flow back into the pipe while the system is being flushed.
The sprinkler heads may also be rinsed under a water faucet to be cleaned out. Unscrew he inside of the head from the outer casing and rinse both pieces. When the flushing complete, re-install the heads and run sprinkler system for approximately 10 minutes per zone.
Turn off the system, if some of the sprinkler heads are still stuck, hey are probably beyond fixing and need to be replaced.