Built to meet the rigorous demands of professional cleaning, the SIMPSON® pressure washer combines a powerful 420cc OHV Commercial Series engine with a durable AAA triplex pump and adjustable unloader. Delivering up to 4,400 PSI and 4.0 GPM, it is designed to tackle demanding cleaning jobs quickly and efficiently.

A heavy-duty welded steel frame, steel axle, 13-inch pneumatic tires, onboard accessory storage, and a professional-style spray gun provide the durability, mobility, and convenience needed for extended cleaning applications. The included 50-foot Monster steel-braided hose and five stainless-steel quick-connect nozzles make it ready for a wide variety of cleaning tasks.

Key Features

SIMPSON® 420cc OHV Commercial Series Engine

The 420cc OHV Commercial Series engine delivers reliable power for professional cleaning applications.

• 420cc OHV engine
• Recoil starter
• 1.71-gallon fuel tank
• Low-oil shutdown for added engine protection
• 3-year limited engine warranty

AAA Triplex Pump with Adjustable Unloader

The AAA triplex pump is engineered for demanding pressure-washing applications and provides adjustable pressure to match the cleaning task.

• Up to 4,400 PSI
• Up to 4.0 GPM
• Adjustable unloader
• Runs cooler than axial-style pumps
• Rebuildable design
• 5-year limited pump warranty

Heavy-Duty Welded Steel Frame

The rugged welded steel frame is built to withstand demanding job-site conditions.

• Heavy-duty welded steel construction
• Steel axle
• Unique handle system
• Handle design helps protect the pump while providing additional leverage
• 10-year limited frame warranty

13-Inch Pneumatic Tires

Large 13-inch pneumatic tires provide easy maneuverability across varied terrain while helping absorb vibration during operation.

Onboard Accessory Storage

Integrated storage keeps essential accessories organized and accessible.

• Nozzle holder
• Spray gun hooks
• Hose storage
• Convenient onboard organization

Five Stainless-Steel Quick-Connect Nozzles

Five included nozzles provide different spray patterns for a range of cleaning applications:

• 0° nozzle
• 15° nozzle
• 25° nozzle
• 40° nozzle
• Soap nozzle

Pro-Style Spray Gun & Wand

The professional-style spray gun features an ergonomic grip and safety lock-out for improved comfort and control.

• Ergonomic comfort grip
• Safety lock-out
• 31-inch wand lance
• M22 connector
• Compatible with many accessories

Monster Steel-Braided Hose

The included 3/8-inch x 50-foot Monster Hose uses wire-reinforced construction for flexible durability.

• 50-foot length
• 3/8-inch diameter
• Wire-reinforced construction
• Quick-connect fittings
• Flexible and durable design

Cleaning Applications

The SIMPSON pressure washer is designed to tackle a variety of stubborn outdoor cleaning challenges, including:

• Dirt and mud
• Mildew
• Algae
• Mold
• Stains
• Watermarks
• Moss
• General residential and professional cleaning

Technical Specifications

Engine & Performance

Frame & Mobility

Hose & Spray Equipment

Warranty Coverage

Note: The supplied specifications also list a 90-day consumer and commercial warranty, while the component-specific warranty information lists longer coverage for the engine, pump, and frame. The component-specific warranties are presented above as provided by the manufacturer information.

Model & Product Information

Built for Tough Cleaning Jobs

From removing stubborn mud and mildew to tackling moss, algae, mold, stains, and watermarks, this SIMPSON pressure washer is designed for demanding cleaning work. Its combination of a commercial-grade 420cc engine, rebuildable AAA triplex pump, adjustable pressure, rugged steel frame, and professional spray equipment provides a complete solution for serious cleaning applications.

Why Choose the SIMPSON 4400 PSI Pressure Washer?

• Up to 4,400 PSI and 4.0 GPM
• Powerful 420cc OHV Commercial Series engine
• Low-oil shutdown protection
• AAA triplex pump with adjustable unloader
• Rebuildable pump design
• Heavy-duty welded steel frame
• Steel axle and 13-inch pneumatic tires
• Onboard hose, gun, and nozzle storage
• Pro-style ergonomic spray gun
• 31-inch M22 wand lance
• 3/8″ x 50′ Monster steel-braided hose
• Five stainless-steel quick-connect nozzles
• Designed for demanding professional cleaning applications
• Long-term pump and frame warranty coverage

Maximum pressure and flow ratings are manufacturer specifications. Actual performance may vary depending on operating conditions, water supply, nozzle selection, and application.