Part Number: 7644
Category: Pressure Washer Accessories → Spray Nozzles → High-Pressure Spray Nozzles
Type: PNR 1/4" MNPT 15° 5.5 Stainless Steel Spray Nozzle – Pressure Washer Replacement Nozzle

The PNR Stainless Steel Spray Nozzle (Part #7644) is a genuine OEM high-pressure replacement nozzle engineered for commercial, industrial, agricultural, and residential pressure washing applications. Featuring a 15-degree fan spray pattern and a 5.5 orifice, this nozzle produces a concentrated, high-impact spray that delivers superior cleaning power for removing stubborn dirt, grease, oil, mud, mildew, and heavy grime from durable surfaces.

Key Features & Benefits

• Genuine PNR OEM high-pressure spray nozzle
• Part Number: 7644
• Concentrated 15° fan spray pattern
• 5.5 orifice size
• 1/4" MNPT connection
• Manufactured from AISI 416 stainless steel
• Precision-machined for consistent spray performance
• Corrosion and wear resistant
• Excellent for removing stubborn dirt, grease, and heavy buildup
• Ideal for commercial and industrial pressure washing
• OEM-quality construction for long service life

Technical Specifications

Part Number: 7644

Manufacturer: PNR

Product Type: High-Pressure Spray Nozzle

Thread Size: 1/4" MNPT

Spray Pattern: 15°

Orifice Size: 5.5

Nozzle Size: 5.5

Material: AISI 416 Stainless Steel

OEM Replacement: Yes

Compatible Applications

Suitable for use with:

• Pressure washer spray guns
• Pressure washer spray wands
• Pressure washer lances
• Commercial pressure washers
• Industrial cleaning equipment
• Heavy equipment cleaning
• Concrete and masonry cleaning
• Agricultural equipment cleaning
• Fleet washing
• General-purpose pressure washing

Always verify the thread size, nozzle size, operating pressure, and machine flow requirements before ordering.

Function of the Spray Nozzle

The PNR 7644 spray nozzle helps:

• Produce a concentrated 15° high-pressure fan spray
• Remove stubborn dirt, grease, oil, mud, and grime
• Deliver aggressive cleaning performance with moderate surface coverage
• Maintain consistent operating pressure and water flow
• Improve cleaning efficiency on hard, durable surfaces

Its 15° spray pattern provides greater cleaning force than wider fan nozzles, making it well suited for concrete, industrial equipment, construction machinery, and other demanding cleaning applications.

Common Signs Replacement Is Needed

Replace the nozzle if you notice:

• Uneven or distorted spray pattern
• Reduced cleaning pressure
• Worn or enlarged orifice
• Clogged nozzle
• Damaged threads
• Corrosion or physical damage
• Increased water consumption caused by nozzle wear

Replacing a worn nozzle restores proper operating pressure, spray pattern, and cleaning performance.

Installation & Service Notes

• Turn off the pressure washer and relieve system pressure before replacing the nozzle.
• Verify compatibility with the 1/4" MNPT connection and 5.5 orifice size.
• Install the nozzle securely without overtightening the stainless steel threads.
• Inspect the nozzle seat and threads for debris before installation.
• Test the spray pattern after installation to verify proper operation.
• Replace the nozzle if wear causes pressure loss or an inconsistent spray pattern.

Important: Match the 5.5 orifice size to your pressure washer's GPM and PSI specifications to maintain proper operating pressure and cleaning performance. The 15° spray pattern is intended for durable surfaces and should be used with caution on painted finishes, soft wood, delicate materials, or other surfaces that may be damaged by concentrated pressure.

Maintenance Recommendations

• Flush the nozzle with clean water after each use.
• Inspect the orifice regularly for mineral deposits, debris, or wear.
• Clean clogged nozzles using an approved nozzle cleaning tool—avoid using wire or sharp objects that may enlarge the precision orifice.
• Store the nozzle in a clean, dry location when not in use.
• Use only genuine OEM replacement nozzles to maintain proper spray pattern, operating pressure, and long service life.