Irrigation sprinkler systems are vital for keeping lawns and gardens healthy, lush, and green during warm weather months. Over time, the valves in these systems can wear out or become damaged and may need replacing. Rebuilding or replacing sprinkler valves is a fairly straightforward DIY project for homeowners with basic mechanical skills and proper instructions.
When to Consider Replacing or Rebuilding Sprinkler Valves
There are a few signs that indicate it may be time to rebuild or replace the valves in your lawn irrigation system:
- The valve is leaking constantly, even when the system is off. This usually indicates worn out seals or valve components.
- The valve does not fully open and close, restricting water flow. Valve components may be stuck or damaged.
- The valve makes loud noises or chattering sounds when operating. There is likely debris stuck in the valve, or components are heavily worn.
- Sections of the lawn show signs of underwatering. A damaged valve may not be allowing enough water to its zones.
- The valve no longer responds to electronic activation signals. Internal control mechanisms may be broken.
Rebuilding valves can often extend their lifespan. But if damage is severe or components are too corroded, full replacement will be necessary.
Valve Rebuilding vs. Replacement
Rebuilding Valves
Rebuilding involves disassembling the valve, inspecting its interior components, replacing any broken parts, lubricating parts and seals, then reassembling the valve.
Advantages of rebuilding:
- Less expensive than full replacement
- Retains existing valve body/housing
- Restores valve to like-new functioning
- Does not require altering pipe fittings
Disadvantages:
- Requires disassembly skills and proper tools
- Worn valve bodies may still fail after rebuilding
- Finding compatible replacement parts can be difficult
- Time consuming process
Replacing Valves
Replacing entails cutting out the old valve then installing a brand new valve in its place. Sweat soldering or threading new pipe fittings is required.
Advantages of replacing:
- Fresh start with all new components
- Long-lasting solution when old valve is too damaged
- Easier process than rebuilding old valves
- Universal replacement valves widely available
Disadvantages:
- More expensive than rebuilding existing valve
- Pipe cutting and fitting skills required
- Alterations to irrigation piping layout
For minor leaks or flow issues, rebuilding is usually the best option. But for major internal damage or corroded valves, replacement is the smarter long-term solution.
Materials and Tools Needed
Rebuilding or replacing irrigation valves requires some specific materials and tools. Having these items on hand will make the process smoother.
Materials
- Replacement valve (for total replacement projects)
- Valve rebuild kit with seals, springs, diaphragms
- Teflon pipe thread tape
- Copper pipe pieces, couplings, elbows (if altering piping)
- Emery cloth or fine grit sandpaper
- Silicone grease or other lubricant
- Rag and cleaner/degreaser
Tools
- Slotted screwdrivers
- Needle nose pliers
- Utility knife or razor blades
- Wire cutters
- Pipe cutter (for replacement jobs)
- Wrenches for disassembly
- Soldering torch, flux, emery cloth (for new fittings)
- Small bucket to hold valve parts
- Valve box lid lifter tool
Finding the Sprinkler Valve Location
Before beginning work on the valve itself, you need to locate it within your irrigation system setup.
- Trace back from sprinkler heads – The pipe leading directly to a sprinkler head will also lead back to its zone valve. Follow this pipe through any twists and turns, keeping note of the path. Mark the pipe with arrows pointing toward the valve if needed.
- Look near hose bibs – Many irrigation valves are located close to external hose bibs for convenient access. Check around any exterior faucets.
- Refer to control wires – Valves are connected via low-voltage control wires that lead back to the irrigation controller. Following these wires can lead you to the valve boxes.
- Look for valve boxes – Most valves are housed in round plastic boxes buried in the ground around the perimeter of the irrigated area. Use your valve box lifter tool to raise lids and peer inside.
- Review original plans – Consult the original irrigation plans if you have them for details on valve configurations and locations.
Once you’ve found the correct valve, shut off the water supply and relieve pressure before beginning work.
How to Rebuild Sprinkler Valves
Rebuilding irrigation valves involves careful disassembly, inspection, cleaning, replacement of worn parts, lubrication of components, and proper reassembly. Here are the step-by-step instructions:
1. Shut off water supply and deactivate system
Locate the main water shut off valve for your irrigation system and turn it off. Also switch the controller off so it does not accidentally activate. Open a downstream sprinkler head to relieve pressure in the pipes.
2. Remove valve lid and unscrew bonnet
Use a specialized tool to lift the valve box lid. Then use pliers or a wrench to loosen and unthread the bonnet (top threaded portion) from the valve body.
3. Disassemble valve interior components
Remove any flow control mechanisms, springs, seals, diaphragms etc. from inside the valve body and place them in your parts bucket. Be organized and keep parts together.
4. Inspect components and body for damage
Look for cracks, abnormal wear, corrosion, or scale buildup on the various valve components and interior surfaces. Damage parts will need replacement.
5. Scrub valve body and parts
Use a degreaser, toothbrush, and rag to remove grime and mineral deposits from all components. Thorough cleaning is vital.
6. Replace any damaged or worn parts
Refer to your valve rebuild kit and switch out any parts that are cracked, warped, worn out, or failing to function. Be sure to get identical replacements.
7. Lubricate components
Lightly coat o-rings, seals, pressure diaphragms, and moving parts with silicone grease. This prevents sticking and reduces wear.
8. Reassemble valve
Insert components in proper order and orientation. Be mindful of right-side-up positioning. Consult valve diagrams if unsure.
9. Hand tighten bonnet
Initially tighten the bonnet by hand with pliers. You want a snug fit but not overly tightened yet.
10. Restore water and test
Turn the main water supply back on and activate the valve electronically. Let water run through valve to flush interior. Check for leaks.
11. Tighten bonnet and retest
If no leaks, use pliers to tighten the bonnet an additional 1/4 turn. Test again while manually operating the valve open and closed. Ensure smooth operation.
12. Reinstall valve and perform final test
Screw the valve back into the box, reattach all wires, close up box lids. Activate entire irrigation zone from the controller and check for smooth operation without leaks.
Installing New Replacement Valve
For completely new valves, the installation process involves cutting out the old valve, preparing and fitting new piping, and adjusting components for optimal function.
1. Shut off water and relieve pressure
Just like with rebuilding, you first want to deactivate the system and relieve water pressure before cutting into pipes.
2. Expose pipes and cut out old valve
Dig around valve box to access pipes. Cut pipe on both sides of existing valve to fully remove it.
3. Clean pipe ends
Use emery cloth or sandpaper to smooth cut pipe ends so they fit cleanly into new fittings. Remove any burrs or debris.
4. Dry fit new valve
Initially thread on new fittings and valve to check alignment and fit. Do not use pipe sealant yet so you can readjust if needed.
5. Apply thread sealant
When positioning is correct, wrap pipe threads with 2-3 overlapping layers of Teflon tape. This prevents leaks.
6. Solder copper fittings if altering configuration
For convenience or to alter layout, you can cut in new copper elbows, couplings, and pipe pieces using a torch.
7. Install valve and tighten fittings
Thread new valve into fittings. Tighten by hand first, then use wrenches to finish tightening per manufacturer specs.
8. Activate water and test
Just like when rebuilding, turn on water and activate valve electronically to flush and check for leaks before completing project.
9. Adjust flow control
Most new valves have a flow-limiting control knob. Adjust to restrict water to recommended volume for optimal pressure.
10. Install valve box and make final adjustments
House new valve back in box, bury box in ground, attach wires, secure lid. Activate entire system one zone at a time to verify proper function.
Rebuilding old valves or installing replacement valves both require careful attention to detail. But these processes can restore smooth operation to your irrigation system.
Troubleshooting Valve Problems
During and after rebuilding or replacing valves, issues can arise. Here is how to troubleshoot some common valve problems:
Valve leaks water when irrigation system is off:
- Seals, o-rings, or seat washer not properly seated or damaged
- Adjust/tighten bonnet to compress seal components
- Drain system and rebuild valve again if needed
Water flow through valve is restricted:
- Debris lodged in valve
- Diaphragm, seals, or springs misaligned or installed upside-down
- Shut off water, disassemble valve, clean and realign parts
Valve turns on and off repeatedly:
- Valve not closing fully allowing pressure to rebuild
- Tighten bonnet to provide tighter seal force
- Replace worn diaphragm or seals
Valve operates noisily:
- Worn diaphragm fluttering in water flow
- Damaged internal components
- Restricted water flow vibrating internal parts
- Rebuild/replace valve and ensure unrestricted water flow
Water pressure surges when valve operates:
- Flow control adjustment knob set too low
- Open flow control setting to increase gallons per minute
- Install larger flow control device if necessary
Valve fails to open electronically:
- Solenoid burnt out
- Faulty wiring connections
- Replace solenoid or correct wiring issues
Preventing Future Valve Repairs
Proper preventative maintenance helps minimize repairs and extend valve lifespan. Here are some tips:
- Inspect valves yearly – Power off water and open boxes to look for leaks, stuck parts, debris, etc. Perform minor maintenance.
- Lubricate diaphragms and o-rings – Keep them supple and prevent binding.
- Flush valves regularly – Open bleed ports or disassemble valves to flush out debris and mineral deposits.
- Adjust water pressure – Excess pressure wears out components faster. Use pressure reducing valves to keep PSI under 60.
- Winterize the system – Drain all water from pipes and valves before winter to prevent freeze damage.
- Update old valves – Replace very outdated valves with modern globe-style anti-siphon valves for optimum performance.
- Filter the water supply – Installing whole-house sediment filters keeps abrasive particles from wearing down valves internally.
- Shut off water when not in use – Prevent constant pressure on components by using the main shut off valve.
- Fix leaks promptly – Small leaks indicate worn parts that will worsen if not addressed quickly.
With proper maintenance, irrigation system valves can last upwards of 15-20 years. But periodically rebuilding or replacing worn valves will keep your system operating smoothly for many seasons.
Frequently Asked Questions
When should you rebuild vs replace a sprinkler valve?
It is best to rebuild valves that have minor leaks, flow restriction, or noise issues. Rebuilding is faster, cheaper and restores the valve to like-new condition. If the internal components are too corroded or worn out, replacement is the better option for longevity.
What are signs that an irrigation valve needs replaced?
Constant water leaks when the irrigation system is off, pieces of broken internal plastic components in the valve, inability of the valve to fully open and close during operation, and no response when valves are electronically activated all indicate replacement is needed.
How much does it cost to replace a sprinkler valve?
For just the replacement valve itself, costs range from $25-$60 on average. Factor in another $20 or so for fittings and pipe sealant. Hiring an irrigation professional will add $150-$300 for labor to remove the old valve and install the new replacement.
Can I install a sprinkler valve myself?
Yes, with some basic DIY skills, the average homeowner can replace irrigation valves. You need to be able to safely cut into pipes, apply new fittings and adapters, solder copper if altering layout, and follow all typical valve installation steps. Irrigation valve manufactures also provide installation instructions.
What tools do I need to rebuild a sprinkler valve?
Typical tools include slotted screwdrivers, needle-nose pliers, utility knives, silicone grease, valve lubricant, a small bucket to hold valve parts, rags, pipe wrenches, a valve box lid removal tool, emery cloth, and a cup to place small parts in. Having a parts diagram is also extremely helpful.
How do I troubleshoot a sprinkler valve that won’t close?
If water continues flowing through a valve even when it should be closed, the diaphragm, seals, and o-rings likely need replacement. Shut off water, disassemble the valve, grease and properly reseat the seals and diaphragm, then reassemble and test valve function again. The bonnet also may need tightened down more firmly.
What PSI should sprinkler valves be set at?
Most irrigation valves are designed to operate at water pressures between 40-60 PSI. Excessive pressure can damage valve components. Use a pressure reducing valve after the main water shut off to maintain optimal PSI.
How can I prevent my sprinkler valves from failing?
Regular lubrication of o-rings, proper winterization, routine flushing of debris from valves, managing water pressure, updating very old valves, installing water filtration, fixing leaks quickly, and performing annual inspections will together help minimize repairs and extend valve life significantly.
Conclusion
Regularly maintaining and promptly repairing irrigation valves keeps sprinkler systems functioning reliably for years. Rebuilding worn valves or replacing severely damaged valves restores optimal performance. While not overly complicated jobs, rebuilding and replacing valves does require proper tools, materials, and following key steps carefully to prevent leaks and other operational issues. Investing a little time upfront in valve maintenance prevents major headache down the road.