Unloader Valves for Pressure Washers

Regulate pressure and protect your pump with professional unloader valves designed for commercial pressure washing applications. Our comprehensive selection includes flow-sensitive unloaders, pressure-actuated unloaders, mounting blocks, and repair kits from General Pump, Comet, and other trusted manufacturers in flow rates from 2 to 26.4 GPM and pressure ratings up to 8000 PSI.

K Series Flow-Sensitive Unloaders

• K7.1 Unloader: 3.0-5.5 GPM at 3500 PSI for compact pressure washers
• K7.2 Unloader: 5.5-8.0 GPM at 3500 PSI for mid-size commercial units
• K7.3 Unloader: 8.0-10.8 GPM at 3500 PSI for high-flow applications
• Professional Grade: K series unloaders deliver precise pressure regulation and long service life
• Easy Adjustment: Simple pressure adjustment without disassembly

General Pump Flow-Sensitive Unloaders

• ZK1 Unloader: 2-10 GPM at 3600 PSI max for versatile applications
• ZH288 Blue Spring: 21 GPM at 4500 PSI with improved design and reduced pressure loss
• Pulsar PLSRZ2140: 5.3-21 GPM at 4050 PSI for commercial pressure washers
• Comet VHP51: 26.4 GPM at 8000 PSI maximum capacity for extreme applications

Pressure-Actuated (Trapped Pressure) Unloaders

• VRT3-310EZ Black Spring: 4500 PSI with built-in easy start valve for easier pull starts
• VRT100 Green Spring: 26.4 GPM max flow at 4500 PSI with 1/2" FPT connections
• VR54 Unloader: 8 GPM at 2900 PSI with 3/8" connections for smaller units
• Trapped Pressure Design: Maintains system pressure when gun is closed for instant response

Unloader Mounting Blocks & Components

• 3/8" Female Unloader Mounting Blocks: Nickel-plated steel and brass options
• 1/2" Female Unloader Mounting Blocks: Nickel-plated steel and brass for larger unloaders
• K7 Orifice #1-2: Replacement orifices for K7 series unloaders
• Comet ZWD-K/AXD/BXD Cartridge: Cartridge unloader for Comet pumps

Unloader Repair Kits & Accessories

• VRT3-310 Repair Kit: Complete rebuild kit for VRT3-310 unloaders
• PLSRZ2140 Rebuild Kit: Repair kit for Pulsar unloaders
• 6,000 PSI In-Line Pressure Gauge: Stainless steel gauge with quick connects for pressure monitoring
• Cost-Effective Maintenance: Rebuild unloaders instead of replacing entire units

Flow-Sensitive vs. Pressure-Actuated Unloaders

• Flow-Sensitive (K7, ZK1, ZH288): Sense flow changes when gun closes, ideal for single-operator use
• Pressure-Actuated (VRT3, VRT100, VR54): Maintain trapped pressure for instant response, better for multi-gun setups
• Application Matters: Choose based on your pressure washer configuration and usage

Why Unloader Valves Are Essential

• Pump Protection: Prevent pump damage from deadheading when trigger gun is closed
• Pressure Regulation: Maintain consistent operating pressure throughout the job
• Bypass Operation: Divert water flow when gun is closed to prevent overheating
• Adjustable Pressure: Set and maintain desired operating pressure
• Equipment Longevity: Proper unloader operation extends pump and component life

Choosing the Right Unloader

• Flow Rating: Match unloader GPM rating to your pump's flow capacity (2-26.4 GPM)
• Pressure Rating: Ensure unloader is rated for your system's maximum PSI (2900-8000 PSI)
• Unloader Type: Flow-sensitive for single operator, pressure-actuated for multi-gun or instant response
• Connection Size: Verify thread sizes match your pump and plumbing (3/8" or 1/2")
• Special Features: Consider easy start valves or specific brand compatibility

Whether you're replacing a failed unloader, upgrading to a K series for better performance, or building a custom pressure washer system, our unloader selection covers every flow rate and pressure rating for professional applications. From compact K7.1 unloaders for 3 GPM machines to massive Comet VHP51 units rated for 8000 PSI, every unloader is designed to protect your pump and maintain consistent pressure. We stock flow-sensitive unloaders for precise regulation, pressure-actuated unloaders for instant response, mounting blocks, repair kits, and all the components needed to keep your pressure washer running reliably.

Need other pressure washer parts? Browse our pump parts, thermal relief valves, pressure switches, and complete product catalog.