Introducció
This manual provides essential information for the installation, operation, maintenance, and troubleshooting of the Watts LFN45B Pressure Reducing Valve. This valve is designed for residential and light commercial applications to regulate water pressure effectively and safely.
Producte acabatview

Figure 1: Watts LFN45B Pressure Reducing Valve. This image displays the bronze-bodied valve with its black adjustment cap and threaded union connections on both sides.
The Watts LFN45B is a compact and versatile pressure reducing valve featuring a bronze body construction. It includes an integrated filter and bypass mechanism. The valve is equipped with NPT union female inlet and female outlet threads for easy installation. It is suitable for water systems with a temperature range of 33 to 180 degrees Fahrenheit and a maximum working pressure of 400 psi. The standard pressure reduction is 50 PSI, adjustable from 25 to 75 psi. A bypass function is incorporated to manage thermal expansion pressure when the inlet pressure exceeds 150 PSI. The valve meets the requirements of ASSE 1003 (ANSI a112.26.2) and IAPMO standards.
Materials: The valve is constructed from durable materials including Bronze, Copper Alloy, and Stainless Steel for the body and internal components. The seat trim is Thermoplastic, softgoods are Elastomer Disc, and the diaphragm is Reinforced EPDM.
Configuració i instal·lació
Proper installation is crucial for the optimal performance and longevity of the Watts LFN45B Pressure Reducing Valve. It is recommended that installation be performed by a qualified professional in accordance with local plumbing codes.
- Ubicació: Install the valve in an accessible location to allow for future maintenance and adjustments.
- Orientació: The valve can be installed in any orientation (horizontal, vertical, or diagonal) as long as the flow arrow on the valve body points in the direction of water flow.
- Connexions: Utilize the NPT union female inlet and female outlet threads for secure connections. Ensure all connections are watertight.
- Colador: The integral stainless steel strainer is designed to protect the valve from debris. It is removable for cleaning by removing the bottom plug.
- Funció de bypass: The integrated bypass function helps control thermal expansion pressure. Ensure adequate space for this function if thermal expansion is a concern in your system.
Instruccions de funcionament
The Watts LFN45B valve is factory set to a standard reduced pressure of 50 PSI. This pressure can be adjusted within a range of 25 to 75 psi.
- Ajust de pressió: To adjust the outlet pressure, loosen the locknut on the adjustment screw located at the top of the valve.
- Augmentar la pressió: Turn the adjustment screw clockwise to increase the outlet pressure.
- Disminuir la pressió: Turn the adjustment screw counter-clockwise to decrease the outlet pressure.
- Verify Pressure: Use a pressure gauge downstream of the valve to verify the desired pressure setting.
- Secure Setting: Once the desired pressure is set, tighten the locknut to secure the adjustment screw in place.
- Funció de bypass: The bypass function automatically controls thermal expansion pressure until the inlet pressure is above 150 PSI. No manual operation is required for this feature.
Manteniment
Regular maintenance ensures the continued efficiency and reliability of your pressure reducing valve.
- Neteja del colador: The integral stainless steel strainer can be removed and cleaned. To access the strainer, shut off the water supply, relieve pressure, and remove the bottom plug of the valve. Clean any accumulated debris from the strainer and reassemble.
- Seat Module Replacement: The seat module is replaceable, which can extend the life of the valve. Refer to Watts' official documentation or website for detailed instructions on replacing the seat module.
- Inspecció periòdica: Periodically inspect the valve for any signs of leaks, corrosion, or damage. Address any issues promptly.
Resolució de problemes
This section provides guidance for common issues you might encounter with your pressure reducing valve.
| Problema | Causa possible | Solució |
|---|---|---|
| High Downstream Pressure | Valve setting too high; debris in valve; thermal expansion. | Adjust pressure setting; clean strainer; install or check expansion tank. |
| Low Downstream Pressure | Valve setting too low; insufficient inlet pressure; clogged strainer. | Adjust pressure setting; check main water supply; clean strainer. |
| Constant Dripping/Leaking | Worn seat or diaphragm; loose connections. | Replace seat module or diaphragm; tighten connections. |
| No Pressure Reduction | Valve bypass stuck open; internal component failure. | Inspect bypass mechanism; consider professional service or replacement. |
If issues persist after attempting these solutions, contact a qualified plumbing professional or Watts customer support.
Especificacions
| Número de model | LFN45B |
| Marca | Watts |
| Material | Bronze, Copper, Stainless Steel |
| Acabat exterior | Bronze, Stainless Steel |
| Mida de la connexió d'entrada | 1 polzades |
| Tipus de connexió d'entrada | National Pipe Tapered (NPT) |
| Tipus de connexió de presa | FNPT |
| Pressió màxima de funcionament | 400 PSI |
| Nombre de Ports | 2 |
| Interval de temperatura | 33 - 180 degrees F |
| Rang de pressió ajustable | 25 - 75 PSI (Standard 50 PSI) |
| Tipus de vàlvula | Vàlvula de globus |
| Certificacions | ASSE 1003, ANSI a112.26.2, IAPMO, NSF 61, CSA B356 |
Informació de la garantia
The Watts LFN45B Pressure Reducing Valve comes with a Garantia limitada de per vida. For specific terms, conditions, and claim procedures, please refer to the official Watts warranty documentation or visit their official weblloc web. Conserveu el comprovant de compra per a reclamacions de garantia.
Suport i Contacte
For further assistance, technical support, or to inquire about replacement parts, please contact Watts customer service or visit their official weblloc:
- Watts Oficial Weblloc: www.watts.com
- Atenció al client: Refer to the Watts weblloc web amb informació de contacte regional.
When contacting support, please have your product model number (LFN45B) and purchase details readily available.





