Zurn Wilkins 34-NR3XLDU 3/4" NR3XL Pressure Reducing Valve with Double Union FNPT Connection

Why I chose the NR3XL for a home pressure reset

A creeping house pressure reading north of 90 psi had started to show up in the places you’d expect: chattering solenoid valves, noisy pipe runs, and a temperamental tankless heater. I swapped in the Wilkins NR3XL (3/4-inch) to bring things back into a safe, consistent range, and I’ve now run it long enough to evaluate both the install experience and day-to-day performance. In short, it’s a compact, serviceable pressure-reducing valve that does what it says with minimal fuss—provided you plan the unions and tailpieces correctly.

Design and build

The NR3XL is a bronze-bodied, cartridge-style regulator with a threaded bell and an integral stainless-steel inlet strainer. The “DU” configuration ships with double-union FNPT tailpieces, which makes removal and future service straightforward. I appreciate the short lay length; it’s considerably more compact than older PRVs I’ve replaced and fits well in tight meter closets.

The threaded bell is more than a convenience feature. On some regulators, digging into the internals requires odd tools or risky prying; here, a standard wrench gets you inside to the spring and cartridge. The stainless strainer is substantial and catches the initial grit you get after a shutoff or mainline repair. Certs include ASSE 1003, IAPMO, CSA, and NSF/ANSI 61—important if you’re in a jurisdiction that checks.

Installation notes

The double unions are the star of the show for DIY and pro installs alike. With the DU version, both sides are FNPT. If your system is copper sweat, plan to add MIP adapters or use the appropriate interchangeable tailpieces (threaded, PEX, copper sweat, CPVC are available). I went with threaded adapters for speed and left enough straight pipe on both sides to service the unit later.

A few practical tips from the bench:
- Support the piping while you seat the union gaskets. The included flat washers can be fiddly; a small lift on the downstream pipe helps align the faces.
- Don’t apply heat anywhere near the valve with gaskets installed. Sweat your adapters first, cool completely, then assemble the unions.
- Use a quality thread sealant or PTFE tape on any male adapters; the unions themselves seal on the gaskets, not on thread dope.
- Observe the flow arrow. PRVs do not like being installed backward.
- Put a pressure gauge on a hose bib downstream before you think you’re done.

Given the short body, I was able to cut out the old unit, clean up the runs, stub in adapters, and set the unions with room to spare. From shutoff to water back on was under an hour, mostly because the layout cooperated.

Adjustment and performance

Out of the box, the NR3XL was near 50 psi on my setup, but I don’t take factory presets at face value. With a static inlet of about 95 psi, I set the outlet to 60 psi using a hose-bib gauge. The adjustment screw has a predictable response: clockwise for more pressure, counterclockwise for less. Lock it down gently when you’re done.

Performance is what you want in a residential PRV:
- Static pressure holds steady at the set point.
- Under load (shower open plus a toilet flush), I’m seeing about a 10–15 psi dip, which is typical for a valve of this size and class.
- Noise is minimal. The usual high-pitched hiss you get from some regulators at partial flow is absent in my installation.
- Pipe hammer events are reduced, though that’s more about stable pressure than full-on hammer control. If you have abrupt-closing valves, add arrestors at the appliance and an expansion tank at the water heater.

The internal strainer did its job on day one; after the first week, I cracked the inlet union and found a small collection of debris. A quick rinse and it was spotless. If your neighborhood water has frequent main disturbances, schedule a periodic check.

Serviceability

This is where the NR3XL earns its keep. The cartridge-loaded design and threaded bell mean you can replace or inspect internals without cutting pipe. The unions let you drop the entire regulator out in minutes. The bell threads are robust and resisted galling, even after a couple of open/close cycles for curiosity’s sake. It’s the kind of regulator you can keep in good shape for a long time instead of treating as a consumable.

The stainless strainer is accessible once you back off the inlet union—no tiny clips or odd fasteners. It’s durable enough to survive repeated cleanings, and it’s not an afterthought mesh that collapses on the first clog.

Fit, compatibility, and options

• Size: 3/4-inch body. For whole-house use on typical residential demand, it’s appropriate. If your home has unusually high simultaneous draw (multiple high-flow showers, irrigation and laundry at once), consider stepping up to a higher-capacity regulator or parallel runs.
• Tailpieces: The DU version is FNPT. If you want sweat, PEX, or CPVC tailpieces, plan for that up front. Don’t assume unions are sweat just because your old valve was.
• Water quality: The integral strainer helps, but a gritty supply will always shorten regulator life. Keep sediment control in mind upstream if you’ve had chronic issues.

What I liked

• Compact, short lay length makes retrofits easy.
• Double unions simplify both installation and future swaps.
• Predictable adjustment and steady regulation under normal loads.
• Cartridge and threaded bell design make internal service approachable.
• Stainless-steel strainer that actually holds up.
• Proper certifications for potable water and code compliance.

What could be better

• The union washers take a careful hand to seat perfectly; misalignment will weep. Keeping a spare pair on the shelf isn’t a bad idea.
• Unions ship as FNPT in this configuration; more prominent labeling on the box would save confusion for folks expecting sweat ends.
• Like most entry-level residential PRVs, you will feel pressure drop under high simultaneous demand. That’s a capacity choice, not a flaw, but it’s worth planning for if your home routinely runs multiple full-flow fixtures.

Best practices for a trouble-free install

• Use a calibrated gauge to set pressure; treat the factory preset as a starting point.
• Set your static target to 55–65 psi for most homes, then check dynamic pressure with a major fixture open.
• Add a thermal expansion tank near the water heater to prevent pressure creep when the system heats.
• If you have loud solenoid valves (washer, dishwasher), pair the regulator with hammer arrestors at the appliance.
• After initial install, recheck pressure in a week and again after a month; minor settling or debris clearing can nudge the set point.

The bottom line

The NR3XL does what a residential PRV should: tame high street pressure to a stable, quiet, appliance-friendly level, while making installation and maintenance straightforward. Its compact body fits where it needs to, the double unions make future service simple, and the cartridge/strainer combination invites upkeep instead of avoidance. It’s not a high-flow specialist, but for a typical household it hits the right balance of performance, reliability, and serviceability.

Recommendation: I recommend the Wilkins NR3XL for residential users who want a reliable, code-compliant pressure regulator that’s easy to install and maintain. It’s a smart upgrade from aging units and a solid first install for homes without a regulator. If your demand profile is unusually high, consider a larger-capacity model or parallel regulators; otherwise, this one is an easy choice.