--- product_id: 346879771 title: "LF25AUB-Z3 Series 1\" Lead-Free Cast Copper Silicon Alloy Water Pressure Reducing Valve, NPT Female Union x NPT Female Outlet, Polymer Seat, Adjustable Pressure 25 to 75 psi, Maximum 300 psi" brand: "watts" price: "$639.46" currency: USD in_stock: true reviews_count: 10 category: "Watts" url: https://www.desertcart.us/products/346879771-lf25aub-z3-series-1-lead-free-cast-copper-silicon-alloy store_origin: US region: United States of America --- # Durable cast copper silicon alloy Adjustable pressure 25-75 psi Operates 33°F to 180°F LF25AUB-Z3 Series 1" Lead-Free Cast Copper Silicon Alloy Water Pressure Reducing Valve, NPT Female Union x NPT Female Outlet, Polymer Seat, Adjustable Pressure 25 to 75 psi, Maximum 300 psi **Brand:** watts **Price:** $639.46 **Availability:** ✅ In Stock ## Summary > 💧 Master your water pressure, protect your home, and join the smart plumbing revolution! ## Quick Answers - **What is this?** LF25AUB-Z3 Series 1" Lead-Free Cast Copper Silicon Alloy Water Pressure Reducing Valve, NPT Female Union x NPT Female Outlet, Polymer Seat, Adjustable Pressure 25 to 75 psi, Maximum 300 psi by watts - **How much does it cost?** $639.46 with free shipping - **Is it available?** Yes, in stock and ready to ship - **Where can I buy it?** [www.desertcart.us](https://www.desertcart.us/products/346879771-lf25aub-z3-series-1-lead-free-cast-copper-silicon-alloy) ## Best For - watts enthusiasts ## Why This Product - Trusted watts brand quality - Free international shipping included - Worldwide delivery with tracking - 15-day hassle-free returns ## Key Features - • **Built to Last:** Robust cast copper silicon alloy body with stainless steel components ensures long-term reliability under up to 300 psi. - • **Thermal Expansion Bypass:** Smart bypass feature prevents pressure spikes caused by thermal expansion, protecting your plumbing system. - • **Lead-Free & Eco-Conscious:** Certified lead-free construction safeguards your water quality and supports sustainable living. - • **Precision Pressure Control:** Easily dial in water pressure from 25 to 75 psi for optimal system protection and efficiency. - • **Effortless Installation & Maintenance:** NPT female union connections and replaceable seat module make upgrades and servicing a breeze. ## Overview The Watts LF25AUB-Z3 is a 1-inch lead-free water pressure reducing valve crafted from durable cast copper silicon alloy. It offers adjustable pressure settings from 25 to 75 psi, supports up to 300 psi maximum pressure, and operates efficiently between 33°F and 180°F. Featuring a thermal expansion bypass and easy NPT female union connections, it ensures reliable, eco-friendly water pressure regulation for commercial, industrial, and residential plumbing systems. ## Description Product Description This 1 inch lead free brass water pressure reducing valve is the standard model, designed to reduce incoming water pressure to protect plumbing systems and reduce water consumption for commercial, industrial and residential applications. The easy maintenance assembly consists of a replaceable seat module, NPT threaded female union inlet by NPT female outlet and a bypass feature to control thermal expansion pressure. The temperature range is 33 to 180 degrees F (0.5 to 82 degrees C). Suitable for up to 300 psi (20.7 bar), the pressure range can be adjusted from 25 to 75 psi (172 to 517 kPa) with the standard setting at 50 psi (345 kPa). From the Manufacturer For more than 145 years, Watts has provided people around the world with products, systems and solutions that help convey, conserve, control and safely use water. Review: Great valve, install was a breeze, works like a charm! - My house was built in 1966 and had a Watts 3/4" U5B series pressure reducing valve. According to the Watts website, the U5B is a higher performance/capacity model than this LF25AUB-Z3 3/4", and comparing the charts on the volume @pressure, there does appear to be a difference, but it looked small at the pressures that represent my operating environment. My old U5B was no longer regulating pressure, and so everything in my house was being subjected to 120psi that comes off my street. This is relatively close to the 150psi safety release on the hotwater tank and it was wreaking havoc with anything less than contractor grade garden hoses (blowing them apart after a few months in service). I became concerned that the high pressure might also destroy a toilet/sink supply line and in the worst case, flood the house while we were gone. I tried to get a repair kit for my U5B and by all accounts I ordered the right kit, but none of the parts fit. Maybe someone accidentally swapped the parts bags between two kits while comparing, or maybe the U5B I had was so old that the design had changed a bit. For whatever reason, the bell housing dimensions on my U5B did not match the dimensions specs noted by Watts. Even though "3/4" was clearly forged in the side of the valve and the sticker on it clearly read U5B. Anyway, I don't know if the old valve was Lead-Free or not. So I decided it was worth it to just order a new valve. The direct modern replacement for the U5B is going for around $300 +/-, depending on your source, and desertcart didn't have any sources. But the LF25AUB-Z3 3/4" was $80 shipped to my door. So I took a chance and ordered it. Installation was a breeze, turned off the main supply, opened a sink to bleed the pressure off the system, shut off the hot water heater, then just backed off the old unit and put the new one in. The new one is maybe 3/16" shorter in overall length, but there is plenty of slack/give in the copper pipes I have to allow for some differences in size. It's amazing the difference this has made for my appliances and what not. We used to get pretty bad water-hammer, installing arresters helped, but did not eliminate. With the new pressure reducing valve in place there is no more water hammer, my automatic icemaker is working clog-free, and the refrigerator door water dispenser works much better. I may miss the 120psi when it comes to working outside, but so far I love the new pressure and there is room to turn it up a bit. The valve comes factory preset to 50psi and can be adjusted up to 75psi. I don't recall the lower limit. Oh, and I took the old valve apart. To my surprise the diaphragm was perfectly intact. What had failed was the bypass valve. It appears to have rotted/worn away small enough to come apart and it got trapped by the screen. And another interesting fact was that I'm quite sure that screen had never been checked in the 49ish years it had been in service and it was perfectly clean, pretty cool. Review: Perfect Fit, Solid Performance - We live near to the water source on a small mountain where we have high incoming pressure. I have had to buy several of these regulators over the twenty plus years we have lived here. I notice the regulator beginning to fail when toilets start having shut-off problems. They will also shut off at a higher pressure that is noticed when there is a small surge when valves are opened, followed by a fall-off immedatiately afterward. I worked in oil and gas for years and rebuilt regulators before and it looks like these could be rebuilt. As this can be predicted, as described above, one could probably buy a kit and do a quick rebuild and get like-new results. It is a good, perfict-fit, piece of equipment and I have one sitting that I will try to repair. ## Features - LEAD-FREE WATER PRESSURE REDUCTION: The Watts 1" Lead-Free Water Pressure Reducing Valve reduces incoming water pressure to protect plumbing systems and reduce water consumption in commercial, industrial, and residential applications. This assembly includes a removable integral stainless steel strainer, replaceable seat module, thermal expansion bypass, high-temperature diaphragm, and a sealed spring case with stainless steel cage screws for waterwork pit installations. - EASY INSTALLATION AND MAINTENANCE: With versatile end connection options such as PEX, CPVC, and Quick-Connect, this lead-free water pressure reducing valve is designed for straightforward installation with easy handling and in-line serviceability, featuring an NPT female union inlet by NPT female outlet that simplifies the installation process. - THERMAL EXPANSION PROTECTION: The valve includes a bypass feature that effectively controls thermal expansion pressure, permitting the flow of water back through the valve into the main when pressures - due to thermal expansion on the outlet side of the valve - exceed the pressure in the main supply. It has an operating temperature range of 33° F (0.5° C) to 180° F (82° C). - VERSATILE PRESSURE ADJUSTMENT: This valve is suitable for pressures up to 300 psi (20.7 bar) and allows for an adjustable pressure range between 25 to 75 psi (172 to 517 kPa), with a standard setting at 50 psi (345 kPa). - EVERY DROP COUNTS: Water. It's in our name and close to our hearts. Since 1874, Watts Water Technologies has been delivering innovative technologies that make the world's most precious resource safe and accessible. Everything we design is made to keep the Earth's most precious resource safer, cleaner, and more useful for our customers. Our family of brands offers one of the most varied product lines in the world, with world-class, water-related solutions. ## Technical Specifications | Specification | Value | |---------------|-------| | ASIN | B00VWHDFJ8 | | Best Sellers Rank | #16,651 in Industrial & Scientific ( See Top 100 in Industrial & Scientific ) #44 in Industrial Pressure Regulators | | Brand Name | Watts | | Connector Type | Threaded | | Customer Reviews | 4.6 4.6 out of 5 stars (1,018) | | Exterior Finish | Stainless Steel | | Global Trade Identification Number | 00098268330427 | | Inlet Connection Size | 1 Inches | | Inlet Connection Type | National Pipe Tapered | | Item Dimensions | 3.9 x 7.4 x 8.5 inches | | Item Type Name | NPT Female Union x NPT Female | | Item Weight | 5.05 Pounds | | Manufacturer | Watts Water Technologies | | Material Type | Cast Copper Silicon Alloy | | Maximum Pressure | 300 Pound per Square Inch | | Model Number | LF25AUB-Z3 | | Number of Ports | 2 | | Outlet Connection Size | 1 Inches | | Outlet Connection Type | FNPT | | Size | 1 Inch | | Specification Met | SDWA or RLDWA | | Thread Size | 1 Inch | | Thread Type | NPT | | UPC | 098268330427 | | Unit Count | 1.0 Count | | Valve Type | Pressure Reducing Valve | ## Product Details - **Brand:** Watts - **Exterior Finish:** Stainless Steel - **Inlet Connection Size:** 1 Inches - **Inlet Connection Type:** National Pipe Tapered - **Item dimensions L x W x H:** 3.9 x 7.4 x 8.5 inches - **Material:** Cast Copper Silicon Alloy - **Maximum Operating Pressure:** 300 Pound per Square Inch - **Number of Ports:** 2 - **Outlet Connection Size:** 1 Inches - **Outlet Connection Type:** FNPT ## Images ![LF25AUB-Z3 Series 1" Lead-Free Cast Copper Silicon Alloy Water Pressure Reducing Valve, NPT Female Union x NPT Female Outlet, Polymer Seat, Adjustable Pressure 25 to 75 psi, Maximum 300 psi - Image 1](https://m.media-amazon.com/images/I/71lII5XzxML.jpg) ## Available Options This product comes in different **Size, Style** options. ## Customer Reviews ### ⭐⭐⭐⭐⭐ Great valve, install was a breeze, works like a charm! *by J***L on April 26, 2015* My house was built in 1966 and had a Watts 3/4" U5B series pressure reducing valve. According to the Watts website, the U5B is a higher performance/capacity model than this LF25AUB-Z3 3/4", and comparing the charts on the volume @pressure, there does appear to be a difference, but it looked small at the pressures that represent my operating environment. My old U5B was no longer regulating pressure, and so everything in my house was being subjected to 120psi that comes off my street. This is relatively close to the 150psi safety release on the hotwater tank and it was wreaking havoc with anything less than contractor grade garden hoses (blowing them apart after a few months in service). I became concerned that the high pressure might also destroy a toilet/sink supply line and in the worst case, flood the house while we were gone. I tried to get a repair kit for my U5B and by all accounts I ordered the right kit, but none of the parts fit. Maybe someone accidentally swapped the parts bags between two kits while comparing, or maybe the U5B I had was so old that the design had changed a bit. For whatever reason, the bell housing dimensions on my U5B did not match the dimensions specs noted by Watts. Even though "3/4" was clearly forged in the side of the valve and the sticker on it clearly read U5B. Anyway, I don't know if the old valve was Lead-Free or not. So I decided it was worth it to just order a new valve. The direct modern replacement for the U5B is going for around $300 +/-, depending on your source, and Amazon didn't have any sources. But the LF25AUB-Z3 3/4" was $80 shipped to my door. So I took a chance and ordered it. Installation was a breeze, turned off the main supply, opened a sink to bleed the pressure off the system, shut off the hot water heater, then just backed off the old unit and put the new one in. The new one is maybe 3/16" shorter in overall length, but there is plenty of slack/give in the copper pipes I have to allow for some differences in size. It's amazing the difference this has made for my appliances and what not. We used to get pretty bad water-hammer, installing arresters helped, but did not eliminate. With the new pressure reducing valve in place there is no more water hammer, my automatic icemaker is working clog-free, and the refrigerator door water dispenser works much better. I may miss the 120psi when it comes to working outside, but so far I love the new pressure and there is room to turn it up a bit. The valve comes factory preset to 50psi and can be adjusted up to 75psi. I don't recall the lower limit. Oh, and I took the old valve apart. To my surprise the diaphragm was perfectly intact. What had failed was the bypass valve. It appears to have rotted/worn away small enough to come apart and it got trapped by the screen. And another interesting fact was that I'm quite sure that screen had never been checked in the 49ish years it had been in service and it was perfectly clean, pretty cool. ### ⭐⭐⭐⭐⭐ Perfect Fit, Solid Performance *by T***M on March 17, 2026* We live near to the water source on a small mountain where we have high incoming pressure. I have had to buy several of these regulators over the twenty plus years we have lived here. I notice the regulator beginning to fail when toilets start having shut-off problems. They will also shut off at a higher pressure that is noticed when there is a small surge when valves are opened, followed by a fall-off immedatiately afterward. I worked in oil and gas for years and rebuilt regulators before and it looks like these could be rebuilt. As this can be predicted, as described above, one could probably buy a kit and do a quick rebuild and get like-new results. It is a good, perfict-fit, piece of equipment and I have one sitting that I will try to repair. ### ⭐⭐⭐⭐⭐ Check you pressure. If High, BUY THIS! *by S***C on December 20, 2016* Update: 6 years later and this thing is still going strong! Had two instance of faucet exploded before pressure valve replacement. Not a single appliances or faucet leaks since replacement! Update: 18 months later this thing pay for itself. I have been consistently saving between 15-30% on my water bills. No change in water use habits. Even with guests staying over, water bill is still lower compare to same season the year before. This product is probably one of the best single product anyone can buy for their home. It does what it is design to do AND MORE. First, I live up the cliff on the Hudson River side (500+fts above sea level). Water company pump up the water pressure to get the water to us in utility lines. My home pressure reading was 115psi at any giving point. I have an old home and a lot of leaking pipe joints. The house already have the older model Watts 25AUB-Z3 installed. However, I tried many time to adjust the pressure with no luck. I come to the conclusion that the valve original to the 50+ years old home is not working. I then did some home work online and take on the task of replacing the value. Took care of it after some major error (PLEASE make sure you install it on the right direction! I screw that up and end up breaking my water meter and have to call the utility company!). The pressure of all the water lines including my hot water lines drop to 50psi instantly. This save all my pipes, appliances, and stop all the water hammering. ## Frequently Bought Together - Watts LF25AUB-Z3 Series 1" Lead-Free Cast Copper Silicon Alloy Water Pressure Reducing Valve, NPT Female Union x NPT Female Outlet, Polymer Seat, Adjustable Pressure 25 to 75 psi, Maximum 300 psi - Watts LF25AUB-Z3 Water Pressure Reducing Valve NPT Female Union x NPT Female, Polymer Seat, 3/4 Inch --- ## Why Shop on Desertcart? - 🛒 **Trusted by 1.3+ Million Shoppers** — Serving international shoppers since 2016 - 🌍 **Shop Globally** — Access 737+ million products across 21 categories - 💰 **No Hidden Fees** — All customs, duties, and taxes included in the price - 🔄 **15-Day Free Returns** — Hassle-free returns (30 days for PRO members) - 🔒 **Secure Payments** — Trusted payment options with buyer protection - ⭐ **TrustPilot Rated 4.5/5** — Based on 8,000+ happy customer reviews **Shop now:** [https://www.desertcart.us/products/346879771-lf25aub-z3-series-1-lead-free-cast-copper-silicon-alloy](https://www.desertcart.us/products/346879771-lf25aub-z3-series-1-lead-free-cast-copper-silicon-alloy) --- *Product available on Desertcart United States of America* *Store origin: US* *Last updated: 2026-05-16*