There are three different kinds of sprinklers that you can install for residential or commercial irrigation systems – 1) rotor heads, 2) spray heads, and 3) multi-stream spray heads. They are very different in action, pattern, and adjustments, so it is a good idea to identify the type of sprinkler before you adjust it.
Sprinkler Type #1 – Rotors
A rotor will pop up out of its canister and then provide a single stream of water, directed by the nozzles that are placed into head, and rotate back and forth. Rotors are easy to identify because the rotate back and forth.
Most rotors can also be adjusted for the radius that they throw. Most manufacturers have specific tools made to adjust the rotor. It is a good idea to ask your sprinkler contractor for this tool, or to buy one of these when you are purchasing your rotors.
Most rotors meant for home use will come with a rack of nozzles that are used to direct the stream. These nozzle sets also allow you to determine the gallons per minute (GPM), or flow rate, of the water coming out of the rotor. Some companies even make nozzles that are designed to help you conserve water, which is helpful if your municipality requires extra water conservation efforts.
Installing nozzles is very easy, but you should follow the guidelines of the manufacturer of your sprinklers. Nozzles are held in place by a set screw, so unscrewing that screw up and out of the way allows you to either place or replace a nozzle. Remember to screw the set screw back down again. You can use the set screw to diffuse some of the spray of the head by turning it down into the actual spraying area of the nozzle.
Tools Required for Rotor Adjustment
Get some tools together before you begin to work with your rotors or sprays.
Each manufacturer sells the little tools that adjust their rotors, but you can also use a hex wrench or allen wrench to do the same adjustments on most of them.
Pro tip: The other tool that saves LOTS of time and hurt fingers is the nozzle insertion collar. This tool holds up the spring-loaded head so that you can work on the nozzles and not get hurt in the process. This might end up being your favorite tool ever! You can use the end of the adjustment tool to pull the spring-loaded head up, and then apply the insertion collar.
How to Make Rotor Adjustments
Sprinklers can be adjusted with the water on or off, but we do recommend setting them the first time before they are installed, if possible.
We recommend pre-installing the nozzle before you put your sprinkler in the ground.
Adjusting the arc of a rotor is very easy, but, it is very specific to each rotor. For instance, Hunter has several different kinds of rotors and they all adjust a little bit differently from each other.
How to Set the Rotor Arc Pattern:
- Turn your system on and stand behind the rotor you want to adjust. Make sure you are behind it as the force of the water when it pops up and begins spraying can hurt!
- Turn the rotor head all the way to the left, to complete any cycle the rotor might be doing.
- Find the “right stop” by applying pressure to the top of the head and turning it all the way to the right, until it stops. Do not try to push it beyond this point. The nozzle is now facing the farthest to the right that it will go.
- Look for the “plus” and “minus” signs on the top of the rotor. Right next to those is a tiny keyhole. If you have the rotor’s adjustment tool, place the key end into the opening.
- Hold the head at the “right stop” while you turn the key counterclockwise. Rotate left for higher arc, rotate right to make the arc smaller.
- Release the key from the opening and allow the rotor to go through its motions to see if the arc is what you need. You may need to adjust the arc by repeating the above instructions.
Note: Each manufacture is slightly different. All Hunter & Rain Bird pop-up rotors use the above instructions. Some Toro rotors have a fixed left-hand stop, versus fixed right mentioned above.
Sprinkler Type #2 – Spray Heads
Sprays pop up out of the ground but do not turn around and around. They typically spray like a water fountain, in a circle, extending out over the plants they are watering. Sprays can also be mounted on top of risers or pipes in order to reach hard to get places in a yard. Depending on the make and model of your rotor, nozzles can come in specific spray patterns such as full circle, part circle, quarter circle, and even some specialty nozzles will water a rectangle! There are also variable arc nozzles allow you to select the arc, typically between 0 and 360. Putting on these nozzles is easy.
#1 Adjusting the Spray Nozzle
- Fixed Spray Nozzles (MPR, Matched Precipitation Rate)
- These nozzles cannot be adjusted, they can only be replaced.
- Example: A 8ft, quarter pattern nozzle, will never change. So if you want to increase the distance, or change the radii, you must replace the nozzle.
- Variable Arc Spray Nozzles (Adjustable)
- The nozzles have an adjustable arc pattern, but must be replaced to change the distance.
- Example: An 8ft nozzle can be adjusted to a radii from 0-360 deg, but the distance will remain 8ft.
#2 Setting the Arc Position
- The stem can be rotated by hand to aim and align the arc radius.
Sprinkler Type #3 – Multi-Stream Spray Head
Multi-stream nozzles are an alternative to traditional sprinkler heads and pop up sprinkler heads that spray the landscape. These nozzles feature unique, multi-trajectory rotating streams that deliver water at a steady rate. This slower application rate allows water to gently soak in at rates that soils can absorb. Use the multi-stream nozzles to replace the sprinkler head on any conventional spray head body.