AR21669 | VR35 NPT Unloader Valve, 4000 PSI

AR21669 | VR35 NPT Unloader Valve, 4000 PSI

The Annovi Reverberi AR21669 VR35 NPT Unloader Valve is a professional-grade
pressure regulation and safety component designed to protect pumps, hoses, and operators in
high-pressure cleaning systems. With a working pressure capacity of up to
4,000 PSI, it is engineered for contractor-grade rigs, industrial wash
stations, and facility maintenance setups where reliability and safety are critical.

Unlike standard unloaders that may rely on specialized fittings, the AR21669 uses
NPT-threaded connections—the most common thread standard in North American
pressure washer systems. This ensures easy integration, replacement, and servicing across a
wide range of platforms, making it a go-to option for professional mechanics, service centers,
and operators who demand compatibility and long-term performance.

Key Features

• Pressure Rating: Up to 4,000 PSI for demanding commercial and industrial applications.
• Valve Type: VR35 unloader valve.
• Connections: Standard NPT threading for broad compatibility and simplified installation.
• Function: Automatic bypass reroutes flow safely when the spray trigger is not engaged.
• Seals: Heavy-duty O-rings and gaskets prevent leaks and extend service life.
• Applications: Contractor rigs, industrial cleaning systems, facility maintenance, and professional wash stations.

How It Works

The AR21669 protects the system by diverting pressurized water back into bypass whenever the
spray trigger is released. Without this function, pumps would remain under full system
pressure during idle cycles, leading to overheating, premature wear, or potential failure.
By rerouting the flow, the AR21669 ensures safe, balanced operation and prevents dangerous
pressure spikes.

The VR35 series is known for smooth pressure regulation, providing operators with consistent
spray output during active use. Once the trigger is pulled again, the valve shifts back to
spray mode seamlessly, maintaining steady pressure for uninterrupted cleaning performance.

Construction & Durability

• Body Material: Rugged brass housing engineered to withstand continuous exposure to water, detergents, and pressure fluctuations.
• Sealing System: High-strength seals resist wear from frequent cycling, reducing downtime and maintenance costs.
• Precision Internals: Machined components deliver smooth bypass operation and consistent system regulation.
• Threading: Standard NPT connections simplify integration into most U.S.-spec systems without adapters.

Installation & Adjustment

• Connections: NPT ports allow for easy threading into pumps, manifolds, or plumbing configurations.
• Adjustment: Integrated pressure adjustment screw lets you fine-tune system PSI to meet specific job requirements.
• Maintenance: Periodic inspection of seals and threads is recommended, but the robust design minimizes the need for frequent servicing.

Applications

• Contractor Cleaning Systems: High-flow rigs used in construction, fleet washing, and mobile cleaning.
• Industrial Wash Stations: Equipment cleaning in plants, warehouses, and factories.
• Facility Maintenance: Reliable operation for universities, municipalities, and corporate campuses.
• Rental Equipment Fleets: Standardized NPT threads simplify replacements and reduce downtime.

Benefits

• Enhanced Safety: Prevents pressure buildup that can damage equipment or endanger operators.
• Extended Pump Life: Reduces stress on pump components by allowing safe bypass during idle operation.
• Universal Compatibility: NPT connections make it a versatile choice for North American systems.
• Low Maintenance: High-quality seals and precision internals deliver dependable service in continuous-use environments.
• Professional-Grade Performance: Built to withstand frequent, high-demand use without losing stability or consistency.

Specifications

• Model: AR21669 – VR35 NPT Unloader Valve
• Max Pressure: 4,000 PSI
• Flow Range: Typically supports 3–10 GPM depending on pump setup
• Valve Type: VR35 unloader
• Connections: Standard NPT threading
• Construction: Rugged brass body with heavy-duty seals
• Function: Automatic bypass with adjustable pressure control
• Applications: Contractor-grade, industrial, and commercial cleaning systems

AR21669 | VR35 NPT Unloader Valve, 4000 PSI

✅ The AR21669 VR35 NPT Unloader Valve is a smart solution for contractors and
industrial operators who need high-pressure performance, universal NPT compatibility, and
proven pump protection. Whether replacing a worn valve in a commercial system or installing
it on a new rig, it delivers safety, reliability, and ease of integration in one
professional-grade package.