VRT3-310EZ Unloader Valve 4500 PSI with Thermal Relief Valve & Injector – OEM Replacement Part
Part Number: 5058
Category: Pressure Washer Parts → Unloader Valves → Pressure Actuated Unloader Valves
Type: Mecline VRT3-310EZ Unloader Valve with Thermal Relief Valve & Injector
The Mecline VRT3-310EZ Unloader Valve (Part #5058) is a premium OEM replacement pressure-actuated unloader engineered for professional pressure washer systems requiring high-pressure performance, integrated chemical injection, and enhanced thermal protection. Rated for up to 10.5 GPM, 4,500 PSI, and 194°F, this heavy-duty unloader is designed to provide reliable pressure regulation while protecting pumps and system components in demanding commercial and industrial applications.
Key Features & Benefits
- Genuine Mecline OEM replacement unloader valve
- Pressure-actuated bypass operation
- Integrated thermal relief valve
- Built-in 2.1 mm chemical injector
- Rated for up to 10.5 GPM
- Maximum pressure rating of 4,500 PSI
- High-pressure black spring configuration
- Protects pumps from pressure spikes
- Helps prevent heat buildup during bypass operation
- Simplifies detergent application
- Durable commercial-duty construction
- Suitable for hot and cold water pressure washer systems
Technical Specifications
Part Number: 5058
Manufacturer: Mecline
Model: VRT3-310EZ
Product Type: Pressure Actuated Unloader Valve
Maximum Flow Rate: 10.5 GPM
Maximum Pressure: 4,500 PSI
Maximum Temperature: 194°F
Spring Color: Black
Injector Size: 2.1 mm
Inlet Connections: Dual 3/8" FPT
Bypass Connections: Dual 3/8" FPT
Outlet Connection: 3/8" FPT
Thermal Relief Valve: Integrated
Chemical Injector: Integrated
OEM Replacement: Yes
Integrated Thermal Relief Protection
The built-in thermal relief valve helps protect the pressure washer system by:
- Releasing overheated bypass water
- Reducing the risk of pump damage
- Protecting seals and internal components
- Extending equipment lifespan
- Improving overall system reliability
This feature is especially valuable when equipment operates in bypass mode for extended periods.
Built-In Chemical Injector
The integrated 2.1 mm injector provides:
- Downstream detergent application
- Simplified system plumbing
- Reduced component count
- Efficient chemical draw performance
- Easier installation compared to separate injector systems
Compatible with many pressure washing detergents, soaps, and cleaning chemicals.
What an Unloader Valve Does
The VRT3-310EZ automatically:
- Regulates operating pressure
- Diverts water flow during trigger release
- Protects pumps from pressure spikes
- Reduces stress on hoses and spray guns
- Maintains system safety
- Improves equipment longevity
When the spray gun is closed, water is redirected through the bypass circuit until cleaning resumes.
Common Applications
Commercial Pressure Washing
Ideal for:
- Professional pressure washing contractors
- Fleet washing equipment
- Mobile cleaning trailers
- Property maintenance systems
- Heavy-duty cleaning operations
Industrial Cleaning Systems
Suitable for:
- Manufacturing facilities
- Equipment wash-down stations
- Industrial maintenance operations
- Agricultural cleaning systems
- Construction equipment cleaning
Hot & Cold Water Pressure Washers
Compatible with:
- Hot water pressure washers
- Cold water pressure washers
- Skid-mounted systems
- Trailer-mounted systems
- Custom-built pressure washer units
Performance Benefits
- Reliable pressure regulation
- High-pressure capability up to 4,500 PSI
- Integrated thermal protection
- Efficient detergent injection
- Improved pump protection
- Reduced component wear
- Consistent cleaning performance
- Extended equipment service life
Signs an Unloader Valve Needs Replacement
Replace the unloader if you notice:
- Pressure fluctuations
- Inconsistent bypass operation
- Water leakage around the valve
- Chemical draw problems
- Excessive heat buildup
- Reduced cleaning performance
- Difficulty maintaining pressure settings
- Internal wear or corrosion
Installation Notes
- Shut down the pressure washer and relieve system pressure.
- Verify compatibility with flow and pressure requirements.
- Install using the proper threaded fittings.
- Connect the chemical pickup hose to the injector.
- Verify proper bypass routing.
- Test for leaks and proper pressure regulation.
- Confirm thermal relief valve and injector operation.
Important: Ensure all pumps, hoses, spray guns, and fittings are rated for the intended operating pressure and flow capacity.
Maintenance Recommendations
- Inspect regularly for leaks and wear.
- Verify pressure settings during routine maintenance.
- Clean injector passages as needed.
- Monitor thermal relief valve performance.
- Maintain clean inlet water filtration.
- Replace worn seals and internal components when necessary.
