The process of capping off a sprinkler head permanently disables a specific point of water output within an irrigation system. Homeowners undertake this task primarily due to changes in landscape design. Removing a head is necessary when extending a patio, installing a new garden bed, or correcting an area causing oversaturation or runoff. Sealing the line prevents water from escaping at the unwanted location, ensuring the system’s efficiency is maintained.
Gathering Supplies and Pre-Capping Steps
Preparation for this permanent repair requires materials for a solvent-welded seal. You will need a shovel, a pipe cutting tool (such as PVC pipe cutters or a hacksaw), and a slip-end cap or PVC plug matching the lateral line diameter. The chemical components required are PVC primer, typically purple, and medium-bodied PVC cement, which chemically fuses the plastic parts together. Rags are also helpful for wiping away excess material.
To begin, locate the main water supply valve for the system, often near the backflow preventer, and turn it off completely. Next, find the sprinkler head to be removed and begin carefully digging a wide trench around it. The goal is to fully expose the riser pipe and the lateral line connection, ensuring enough space to work comfortably and make a clean, accessible cut at the junction.
Detailed Procedure for Permanent Sprinkler Head Removal
Once the pipe is fully exposed, the most secure method involves eliminating the threaded riser pipe and sealing the main lateral line. Dig down until the connection point where the riser meets the main buried pipe, often a T-fitting, is visible. Cutting the riser pipe flush with the lateral line allows a slip cap to be cemented directly onto the remaining pipe stub, creating a robust seal.
Before applying any solvent, the cut pipe end and the inside of the new cap must be completely dry and clean. PVC primer is swabbed onto both surfaces; this chemical softens the rigid PVC plastic and prepares it for the cement. The primer must be applied liberally, and the purple dye helps ensure full coverage on all contact points.
Immediately after priming, apply a layer of PVC cement over the primed pipe end and inside the cap. The cement is a solvent that chemically melts the plastic surfaces, requiring quick work before it begins to set. Push the cap onto the pipe stub with a slight twisting motion to evenly distribute the cement and ensure the cap seats fully against the connection point.
Hold the cap firmly in place for at least 30 seconds to prevent “push-back.” After the initial hold, a visible bead of cement should surround the entire circumference of the joint, which can be wiped clean with a rag. For a pressurized irrigation line, the joint requires a significant curing period, often 24 hours, before the system can be repressurized.
The extended curing time allows the chemical weld to fully bond the plastic molecules, which is important in pressurized systems. Once the estimated curing time has passed, slowly turn the main water supply back on while carefully observing the newly capped area for any leaks or seepage. Only after confirming the seal is watertight should the excavated area be backfilled with soil.
Temporary Solutions and System Considerations
For temporary deactivation, a less invasive method can be employed without cutting the main line. This involves removing the existing sprinkler nozzle and installing a simple threaded cap or flush plug directly onto the riser’s threaded connection. This solution stops water flow at the head but keeps the riser intact for potential future use.
Removing a sprinkler head decreases the overall flow requirement on that zone, increasing dynamic water pressure for remaining heads. This pressure change can cause fine misting or atomization of the spray pattern, leading to poor water distribution and overspray. Homeowners should observe the remaining operating heads and may need to adjust the flow rate, replace existing nozzles with lower-gallon-per-minute (GPM) versions, or adjust the arc of the spray to compensate.