Basic sprinkler system maintenance, part 2 - adjusting pop-up spray heads.

Adjusting rotor heads (the heads that turn shooting out a stream of water) is a little more complex than pop-up spray heads.  Depending on the head manufacturer head ajustment may be tool-less, require a specialized key (Hunter PGPs) or a small flat-head screw-driver (Rainbird 3500 & 5000 series).  For the sake of keeping this blog simple we will review how to check adjustment on Rainbird 3500s and 5000s.  I won't be going over nozzling these heads because it is way too easy to disrupt the precipitation pattern in a rotor zone unless you know what you're doing.  The selection of nozzles not only involves distance the water is thrown but also the arc of the rotor (ie a rotor in a 1/4 arc, 90 degrees, will cover the same patch of ground 4 times in the time a full circle rotor covers the ground around it once).

• First, turn on the rotor zone, either manually from the valve or from the controller.
• Walk up to the first rotor head and watch it.  What you are looking for is that the head is perpendicular to the ground and not leaning one way or another, the wiper seal at the base of the rotor is not blown and leaking, that the nozzle is still in the rotor, the stream is reaching adjacent heads (maintaining head to head coverage) and that the head returning after hitting the end of it's arc (ie-it's not hitting the end of it's arc and get stuck in the same position).
• Now that you have checked to see if it's still working correctly let's check the adjustment on the arc.  When the rotor hits the outside of it's arc on either side it should be edge of what that zone is watering, typically with these it will be the edge of the lawn.  if it isn't reaching the edge or is over watering into an adjacent area we are going to have to make some adjustments.
• With all rotor heads one side of the spray is fixed and the other side is the adjustable side.  In other words you will line up the fixed side, on Rainbird 3500/5000s this will be the left side, with the left edge of what you're watering.  This will be to the left from behind the rotor, the dry side.  You can accomplish this by taking a pair of channel locks, grabbing the barrel of the rotor below the top inch or so that has the nozzle in it and carefully turning it.  Now that you have the left edge set, take the small flat-head screwdriver and put it through hole in the rubber cap with the +/- symbols next to it and turn it to adjust the arc.  It only takes a slight twist of the screwdriver to adjust the arc several degrees.  I like to make a slight adjustment and either let the rotor turn or grab the top and swing it to each end of the arc to evaluate coverage.
• Repeat this on each head in the zone, checking for leaks and other damage.

Drip irrigation is pretty simple to check as long as it was installed well.  What you will be checking for is that there aren't any breaks in the drip line and visible emitters are working properly.

• Turn on the drip zone and you should hear air/water starting to spit out of the emitters.
• Walk the length of the drip line, looking for leaks where the line has been damaged or emitters pulled out of the drip line.
• As you're walking, check individual emitters to see if they're dripping, if they aren't replace the clogged emitter.
• Make sure the water is getting delivered where it should be, sometimes plants die or get moved.  If water is no longer needed remove the emitter and replace it with a 'goof plug.' Sometimes 1/4" 'spaghetti tube' gets caught up in a rake and ripped out, if an emitter isn't putting water anywhere near the plant that needs it cut an appropriate length of spaghetti tube and run it from the emitter to the plant.  Secure the lose end with a bug cap and stake or at least a landscape staple.

Voila! Your irrigation should be in pretty decent shape now and if you keep this up yearly your system and landscape will benefit from more uniform watering and less wasted water.  If it has been a really  long time (10+ years) since it's had a tune-up there are probably quite a few components that need replacing and heads moved you may need to get the services of a professional irrigation tech to help you out.