Introduction
This manual provides essential information for the proper installation, operation, and maintenance of the Zurn 1-950XLT2 Wilkins Double Check Valve Backflow Preventer. This device is designed to protect potable water supplies from contamination or pollution due to back-siphonage or backpressure from non-potable sources. Adherence to these instructions is crucial for optimal performance and compliance with local regulations.
The Zurn 1-950XLT2 is suitable for a wide range of applications, including residential, commercial, industrial, irrigation, marine, and fire protection systems. It features a bronze body construction, Noryl replaceable seats, and silicone rubber check discs, ensuring durability and reliable operation.
Safety Information
- Always depressurize the system before attempting any installation, maintenance, or repair.
- Wear appropriate personal protective equipment (PPE), including safety glasses and gloves.
- Ensure all local plumbing codes and regulations are followed during installation and testing.
- Only qualified personnel should install and service this backflow preventer.
- Do not use this device for applications exceeding its specified temperature and pressure ratings.
Product Overview
The Zurn 1-950XLT2 is a double check valve assembly designed to prevent backflow. It consists of two independently operating, spring-loaded check valves, two full port shut-off valves, and four ball valve test cocks for field testing.
Image 1: Front view of the Zurn 1-950XLT2 Double Check Valve Backflow Preventer. This image shows the bronze body, the two main check valve sections, and the green-handled shut-off valves on either end. The model number and pressure rating are visible on the body.
Image 2: Angled view of the Zurn 1-950XLT2, highlighting the full port connections and the overall compact design. The green handles of the shut-off valves are clearly visible.
Image 3: Top view of the Zurn 1-950XLT2, showing the four black-capped ball valve test cocks positioned along the body, essential for testing the check valves.
Installation
Pre-Installation Checks
- Verify that the model number and size match the system requirements.
- Inspect the unit for any signs of damage from shipping.
- Ensure all necessary tools and materials are available.
- Confirm compliance with local plumbing codes for backflow prevention devices.
Mounting and Orientation
The Zurn 1-950XLT2 must be installed in a horizontal position with the test cocks facing upwards to allow for proper testing and drainage. Ensure adequate clearance around the unit for maintenance and testing.
Piping Connections
- Flush the supply line thoroughly to remove any debris before connecting the backflow preventer.
- Install the unit with the flow arrow on the body pointing in the direction of water flow.
- Use appropriate pipe thread sealant on all threaded connections. Avoid overtightening.
- Ensure the shut-off valves are in the closed position during installation.
- Gradually open the upstream shut-off valve to slowly fill the device and system, allowing air to escape through the test cocks.
- Once filled, slowly open the downstream shut-off valve.
Operation
The Zurn 1-950XLT2 operates automatically to prevent backflow. Under normal flow conditions, both check valves are open. If a backpressure or back-siphonage condition occurs, the check valves close to prevent reverse flow.
Shut-off Valves
The unit is equipped with two full port shut-off valves, one upstream and one downstream. These valves allow for isolation of the backflow preventer for maintenance or testing without shutting down the entire water supply.
- To close: Turn the green handle 90 degrees until it is perpendicular to the pipe.
- To open: Turn the green handle 90 degrees until it is parallel to the pipe.
Maintenance
Regular maintenance and testing are essential to ensure the continued proper functioning of the backflow preventer and compliance with local regulations.
Annual Testing
The Zurn 1-950XLT2 must be tested annually by a certified backflow prevention device tester. The four ball valve test cocks are provided for this purpose. Refer to local codes for specific testing requirements and frequencies.
Servicing
The entire unit is designed to be serviceable in-line. This includes the Noryl replaceable seats and silicone rubber check discs. If repairs are needed, use only genuine Zurn replacement parts.
- Isolate the unit by closing both upstream and downstream shut-off valves.
- Depressurize the unit by opening the test cocks.
- Follow the specific service instructions provided in the detailed service manual (available from Zurn) for disassembling and reassembling the check valve modules.
- After servicing, close test cocks, slowly open shut-off valves, and re-test the unit.
Troubleshooting
| Problem | Possible Cause | Solution |
|---|---|---|
| Water leakage from test cocks | Test cock not fully closed; debris in test cock; faulty test cock. | Ensure test cock is fully closed. Flush test cock. Replace test cock if damaged. |
| Continuous discharge from relief valve (if applicable, though this is a DCVA) | Not applicable for Double Check Valve Assembly (DCVA). This symptom is typical for a Reduced Pressure Zone (RPZ) assembly. | N/A (DCVA does not have a relief valve). |
| Failure during annual test | Worn check valve seats or discs; debris lodged in check valves; damaged springs. | Isolate unit, disassemble, inspect, clean, and replace worn components (seats, discs, springs). Re-test after service. |
| Reduced flow or pressure drop | Partially closed shut-off valves; debris accumulation within the unit or upstream piping. | Ensure shut-off valves are fully open. Isolate and flush the system. Inspect check valves for debris. |
For issues not listed here, or if troubleshooting steps do not resolve the problem, contact a certified plumbing professional or Zurn technical support.
Specifications
- Model: Zurn 1-950XLT2 Wilkins Double Check Valve Backflow Preventer
- Material: Bronze
- Inlet/Outlet Connection Size: 1 Inch
- Connection Type: Full Port
- Number of Ports: 2 (for main flow)
- Test Cocks: 4 Ball Valve Test Cocks
- Temperature Range: 33°F to 180°F (0.5°C to 82°C)
- Exterior Finish: Rubber, Silicone (for seals and discs)
- Dimensions (L x W x H): Approximately 10 x 7.5 x 4.5 inches
- Item Weight: Approximately 8.1 pounds
- Certifications: NSF/ANSI 372 (Lead Free), NSF/ANSI 61, ASTM B122, ASTM B153, ASSE 1013, ASSE 1014
- Lead Free Compliance: Yes
Image 4: Informational graphic illustrating key features: "Retrofit" (suitable for retrofit applications), "Lead Free" (low lead compliant), and "Water Saving" (implied benefit of proper backflow prevention). This highlights the product's modern design and compliance.
Warranty and Support
Warranty Information
Zurn products are manufactured to high-quality standards. For specific warranty details, please refer to the official Zurn warranty statement included with your product or visit the Zurn website. Keep your purchase receipt for warranty claims.
Customer Support
For technical assistance, replacement parts, or further information, please contact Zurn customer support. You can find contact details on the official Zurn website or through your local distributor.
Zurn Website: www.zurn.com
