Pop-up sprinkler heads, devices engineered to rise from the ground when pressurized, are a common component of automated irrigation systems. Precise adjustment of these heads is necessary to ensure water is distributed efficiently across a landscape, which directly impacts both water conservation and the health of the lawn. Misaligned sprinklers can lead to wasteful overspray onto hard surfaces or create dry patches in the turf. This guide details the procedures for adjusting the two primary types of pop-up sprinkler heads to achieve optimal performance.
Identifying Your Sprinkler Head Type
Determining the type of head installed is necessary, as the mechanisms for controlling the spray pattern differ significantly. The two main types of pop-up heads are spray heads and rotor heads.
Spray heads apply water simultaneously across the entire pattern, functioning like a fixed showerhead. They typically have a shorter throw distance, ranging from 4 to 15 feet, and are well-suited for smaller, irregularly shaped areas.
Rotor heads, also known as gear-drive sprinklers, apply water in a single, rotating stream over a longer distance. These heads can throw water from about 15 feet to over 70 feet, making them the preferred choice for expansive lawn areas. A rotor head is easily identifiable by the steady, back-and-forth movement of the water stream during operation.
Step-by-Step Adjustment for Spray Heads
Adjusting the radius on a spray head is done using a small flat-head screwdriver. A radius adjustment screw, usually located on the top center of the nozzle, intercepts the upward water stream. Turning this screw clockwise drives it further into the stream, physically disrupting the water flow and shortening the throw distance.
This adjustment allows for a reduction in distance of up to 25% of the nozzle’s maximum range. For example, a nozzle rated for 10 feet can usually be reduced to 7.5 feet, which helps prevent overspray onto walkways or adjacent structures. If the nozzle is a variable arc nozzle (VAN), the arc can be adjusted by manually turning the outer collar or tabs on the nozzle itself.
For heads with fixed spray patterns, the arc cannot be changed. The only way to adjust the direction is to physically align the entire riser and nozzle assembly. This is accomplished by pulling up the riser and rotating it to point the spray pattern toward the desired area. If the head is spraying too much mist, turning the radius screw slightly clockwise can help by lowering the pressure within the nozzle.
Step-by-Step Adjustment for Rotor Heads
Rotor heads require a specialized approach because their arc is defined by mechanical stops. The first step is to establish the fixed right stop, which is the non-adjustable side of the arc. With the system running, the internal mechanism can be rotated manually to its furthest point clockwise, setting the starting position for the arc of spray.
Arc adjustment is done using a specialized rotor adjustment key that fits into a keyhole on the top of the head. This tool is inserted into the adjustment socket, often marked with plus and minus symbols, to set the degree of rotation. Turning the key clockwise increases the arc, while turning it counterclockwise decreases the arc.
Once the arc is set, the throw distance is fine-tuned using the radius adjustment screw. This screw, which is often a hex-shaped hole or a slot for the metal end of the adjustment key, controls the distance of the water stream. Turning this screw clockwise drives a pin or screw into the stream, reducing the throw distance. Turning it counterclockwise increases the distance.
Finalizing Coverage and Troubleshooting
After adjusting the individual sprinkler heads, the entire zone should be run to observe the overall watering pattern. The goal is to achieve “head-to-head coverage,” where the water from one sprinkler reaches the location of the adjacent sprinkler head. This ensures the entire area receives a uniform amount of water, preventing dry spots.
Look for areas where water is pooling excessively near a head or where the spray is falling short of the next head. Minor adjustments to the radius can usually resolve these coverage errors. If the pressure seems low across the entire zone, it could suggest too many heads are operating on the line, though this is a hydraulic issue beyond simple adjustment.
Finally, confirm that all pop-up heads retract completely back into their housing once the water is shut off. A head that remains partially popped up can be damaged by lawnmowers or become a tripping hazard, indicating a need to clear debris or check for a loose seal.