McMaster-Carr logo
    Filter by
    Valve Type
    For Use With
    Body Material
    Fitting Connection
    Thread Type
    Minimum Opening Pressure
    Maximum Pressure @ Temperature
    Connects To
    Valve Function
    Specifications Met
    Maximum Temperature
    Flow Coefficient (Cv)
    Material
    Food Industry Standard
    U.S.–Mexico–Canada Agreement (USMCA) Qualifying
    Minimum Pressure
    DFARS Specialty Metals
    Export Control Classification Number (ECCN)
    Industrial Info Snippet
    Forward
    Enter e-mail addresses in the fields below
    Message
    Cancel
    Print
    How can we improve?
    Comments
    E-mail address (if you would like a response)
    10 Products

    Easy-Maintenance Threaded Two-Stage Backflow-Prevention Valves for Drinking Water

    Image of Product. Front orientation. Backflow-Prevention Valves. Easy-Maintenance Threaded Two-Stage Backflow-Prevention Valves for Drinking Water, Reduced Pressure Zone.

    Reduced Pressure Zone

    Integral shutoff valves isolate flow for inline maintenance, and a top-entry cover provides easy access to internal components. These valves meet NSF/ANSI 61 for use with drinking water. For maximum protection from system contamination, they consist of a primary check valve and a secondary check valve. If the first check fails to close when flow stops or reverses, the secondary check valve engages to prevent backflow. A strainer prevents debris from blocking the check valves.
    Reduced Pressure Zone—Reduced-pressure-zone valves have a relief valve that discharges backflow if both check valves fail.
    Air Inlet—Valves with an air inlet provide high-capacity relief in emergency conditions. If both check valves fail, the inlet introduces air to quickly displace liquid for faster discharge through the relief valve.
    Pipe
    Size
    Max. Pressure
    @ Temp.
    Min. Opening
    Pressure, psi
    Temp. Range,
    ° F
    End-to-End
    Lg.
    Features
    Specs.
    Met
    Food Industry
    Std.
    Certification
    For Use With
    Seal
    Material
    Each
    Bronze Body—Reduced Pressure Zone
     
    NPT Female Inlet × NPT Female Outlet
    1/2
    		175 psi @ 180° F3035 to 18012 3/4"Relief Valve, StrainerASSE 1013NSF/ANSI 61
    		USC Foundation Approved
    		Drinking WaterBuna-N
    		47845K250000000
    3/4
    		175 psi @ 140° F3035 to 14018 1/16"Air Inlet, Relief Valve, StrainerASSE 1013NSF/ANSI 61
    		USC Foundation Approved
    		Drinking WaterBuna-N
    		4777K8100000000
    3/4
    		175 psi @ 180° F3035 to 18016 15/16"Relief Valve, StrainerASSE 1013NSF/ANSI 61
    		USC Foundation Approved
    		Drinking WaterBuna-N
    		45265K41000000
    1
    		175 psi @ 140° F3035 to 14019 5/8"Air Inlet, Relief Valve, StrainerASSE 1013NSF/ANSI 61
    		USC Foundation Approved
    		Drinking WaterBuna-N
    		4777K8200000000
    1
    		175 psi @ 180° F3035 to 18018 1/4"Relief Valve, StrainerASSE 1013NSF/ANSI 61
    		USC Foundation Approved
    		Drinking WaterBuna-N
    		45265K42000000
    1 1/4
    		175 psi @ 180° F3035 to 18021 13/16"Relief Valve, StrainerASSE 1013NSF/ANSI 61
    		USC Foundation Approved
    		Drinking WaterBuna-N
    		45265K4300000000
    1 1/2
    		175 psi @ 180° F3035 to 18022 3/4"Relief Valve, StrainerASSE 1013NSF/ANSI 61
    		USC Foundation Approved
    		Drinking WaterBuna-N
    		45265K4400000000
    2
    		175 psi @ 180° F3035 to 18026 11/16"Relief Valve, StrainerASSE 1013NSF/ANSI 61
    		USC Foundation Approved
    		Drinking WaterBuna-N
    		45265K4500000000
     
    NPT Male Inlet × NPT Male Outlet
    1 1/2
    		175 psi @ 140° F3035 to 14024 3/8"Air Inlet, Relief Valve, StrainerASSE 1013NSF/ANSI 61
    		USC Foundation Approved
    		Drinking WaterBuna-N
    		4777K8300000000
    2
    		175 psi @ 140° F3035 to 14025 15/16"Air Inlet, Relief Valve, StrainerASSE 1013NSF/ANSI 61
    		USC Foundation Approved
    		Drinking WaterBuna-N
    		4777K8400000000
     
    back to top