How to Use Compression Couplings to Repair Lawn Sprinkler Pipe

  • 01 of 07

    Compression Couplings Make it Easy to Repair Sprinkler Pipe

    A compression coupling
    Aaron Stickley

    During a new installation of PVC sprinkler pipes, joints are normally completed using solvent-cement fittings. This becomes less pracical, though, if you are trying to replace a broken segment of pipe when the rest of the lines are already in place. In this situation, there simply is not enough slack to easily insert replacement pipes and glue them in place.

    In this circumstance, a good option is using a PVC compression fitting. This fitting seals by squeezing washers tightly against the pipes, and it requires no measuring or gluing to use. All that's necessary is to cut away the bad section of pipe and insert a compression fitting to replace the bad section. If the damage involves a large section of pipe, you can make the repair with a length of replacement pipe and two compression fittings to join each end of the repair segment to the existing system.

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  • 02 of 07

    Tools and Supplies You Will Need

    Needed for compression coupling installation
    Aaron Stickley

    Materials and tools required are likely already part of your plumbing toolbox: 

    • Hacksaw or PVC pipe cutter
    • Two pairs of channel-type pliers
    • Clean rag
    • PVC solvent cement
    • PVC compression coupling to match pipe size


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  • 03 of 07

    Prepare the Pipe

    Cut Broken Pipe
    Aaron Stickley

    Cut a small gap out of the broken pipe, about 1 inch wide, to make room for the compression coupling. Clean both ends of the pipe, and make sure rough burrs are removed. 

    If the damaged area is large, you can cut out a wide section of pipe, but you will need a length of replacement pipe and two compression fittings to make the repair. 

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  • 04 of 07

    Position the Slip Nuts and Washers

    Compression coupling ends
    Aaron Stickley

    Remove both ends of the compression coupling. Begin by slipping one compression nut over each exposed end of the pipe, with the threaded socket pointing toward the break in the pipe. Next, slip a rubber washer over each exposed end of the pipe, after the compression nut. 

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  • 05 of 07

    Align the Coupling

    The compression coupling in place
    Aaron Stickley

    Insert the compression coupling onto the pipe. Align the center of the coupling with the gap in the pipe.

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  • 06 of 07

    Slide Washers and Nuts into Place

    Compression coupling gaskets
    Aaron Stickley

    While holding the coupling with one hand, first slide the compression washers, then the nuts, onto each end of the coupling. Thread the nuts loosely onto the threaded ends of the fitting.

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  • 07 of 07

    Tighten the Fitting and Check the Seal

    Tighten the coupling ends
    Aaron Stickley

    Use one set of channel-type pliers to hold the center of the coupling in place, while using the second set of pliers to tighten each compression nut onto the filling. Be careful to not over-tighten; it is very easy to break the compression nut if you use too much force. 

    Turn on the water and check for leaks. If you spot seeping, tight the nuts just slightly more. Once you are confident that the joint is not leaking, fill in the excavation and bury the pipe.