Licensed California Contractor #1005582

    Backflow Preventer Repair & Installation in Walnut

    Expert repair of failing backflow devices and code-compliant installation of new backflow preventers by a licensed California contractor.

    What Is Backflow and Why Does It Matter?

    Backflow occurs when contaminated water flows backward into your clean water supply due to a sudden change in water pressure. This can happen during water main breaks, fire hydrant usage, or pressure drops in the municipal system. Without proper prevention, pesticides, fertilizers, sewage, or other hazardous materials can contaminate your drinking water.

    California law requires backflow prevention devices on all commercial properties and many residential properties with irrigation systems, pools, or wells. When your backflow device fails its annual inspection, you need a qualified plumber to repair or replace it quickly—that's where Walnut Plumbing comes in.

    Our Specialty: Repair & Installation

    While we do not perform the annual certification test itself, we specialize in the rapid repair and rebuilding of assemblies that have failed their inspection. Once we restore your device to code, we work with local certified testers to ensure your final paperwork is filed correctly.

    Backflow Preventer Repair & Installation

    Expert Repair of Failing Backflow Devices

    When your backflow preventer fails its inspection, we provide fast, professional repairs using factory parts. Our technicians can rebuild most assemblies on-site, replacing worn rubber seals, springs, and check-valves to restore proper function.

    • On-site repairs with factory replacement parts
    • Rubber seal and gasket replacement
    • Check-valve rebuilding and replacement
    • Spring mechanism restoration

    Code-Compliant Installation of New Backflow Preventers

    Whether you're installing a new irrigation system, pool, or commercial equipment, we design and install the appropriate backflow prevention device to meet local codes. We handle permits and ensure proper installation for your initial certification.

    • Pressure Vacuum Breakers (PVB)
    • Reduced Pressure Zone (RPZ) assemblies
    • Double Check Valve Assemblies (DCVA)
    • Atmospheric Vacuum Breakers (AVB)

    Has Your Backflow Preventer Failed Its Annual Test?

    A failed backflow test doesn't always mean you need a brand new device. In most cases, we can restore your existing assembly to pass re-inspection by replacing the internal components that wear out over time.

    Common Repair Components We Replace:

    Rubber Seals & Gaskets

    Deteriorate from chlorine and minerals in water

    Check-Valve Discs

    Wear from constant opening and closing cycles

    Springs & Spring Guides

    Lose tension over time, causing slow response

    O-Rings

    Crack and harden from age and temperature changes

    Poppet Assemblies

    Develop pitting that prevents proper sealing

    Relief Valve Components

    Mineral buildup prevents proper discharge

    After completing repairs, we coordinate with local certified testers to schedule your re-test and ensure your compliance paperwork is filed correctly with your water district.

    Types of Backflow Prevention Devices

    The type of backflow preventer required depends on the degree of hazard and your local water district's requirements. Our technicians can evaluate your property and recommend the appropriate device for new installations or replacements.

    Device TypeCommon ApplicationsProtection Level
    RPZ AssemblyCommercial, high-hazard residentialHighest
    Double Check ValveFire sprinklers, low-hazard commercialMedium
    Pressure Vacuum BreakerIrrigation systemsMedium
    Atmospheric Vacuum BreakerHose bibbs, small irrigationBasic

    Who Needs Backflow Prevention?

    While commercial properties are always required to have backflow prevention, many residential properties also need protection. You likely need a backflow device if your home has:

    • Underground irrigation or sprinkler systems
    • Swimming pool or spa with automatic fill
    • Solar water heating systems
    • Hot tubs with dedicated water lines
    • Private wells connected to municipal water
    • Fire sprinkler systems
    • Auxiliary water systems or storage tanks
    • Home medical equipment (dialysis machines)

    Why Choose Walnut Plumbing for Backflow Repair?

    When your backflow device fails inspection, you need a licensed plumber who can diagnose and repair the issue quickly. Our technicians have extensive experience rebuilding all major brands and models of backflow preventers.

    • Experienced in all major backflow preventer brands
    • Factory replacement parts for lasting repairs
    • Licensed California Contractor #1005582
    • Coordination with certified testers for re-inspection
    • Family-owned business since 2005
    • Transparent pricing with no hidden fees

    Schedule Backflow Repair

    Failed your backflow test? We can repair or rebuild your device so it passes re-inspection.

    Repair Specialists

    All Major Brands

    We carry factory parts for most backflow preventers and can complete repairs on-site in a single visit.

    Licensed & Insured

    CSLB #1005582

    California State Contractor License

    Failed Inspection?

    Don't delay—water districts set deadlines for repairs. Call us for fast turnaround so you can schedule your re-test.

    Speak with a Local Walnut Expert Today

    We specialize in rapid repair and rebuilding of backflow devices that have failed inspection. Call now to restore your assembly to code.