Guide to pressure washer hose fittings

Choosing the right pressure washer accessories is as crucial as selecting the pressure washer itself. Accessories like nozzles and fittings can significantly enhance your efficiency and ease of use.

What Are Fittings?

Fittings are adapters that connect various parts of a pressure washer. They are essential for:

• Adding attachments (e.g., foamers, surface cleaners, pressure gauges)
• Using different high-pressure hoses or extending existing ones
• Quick connections with screw fittings
• Preventing hose kinks with swivel fittings

Types of Fittings

1. Quick Connect Fittings

   • Function: Allow for fast attachment and removal of hoses or spray guns.
   • Types: Male and female fittings. Female fittings typically include an O-ring to prevent leaks, while male fittings insert into female ones.
   • Benefit: Easy and efficient connection and disconnection.

2. Swivel Fittings

   • Function: Prevent hose kinking and aid in unwinding the hose.
   • Benefit: Allows the hose to spin without twisting the spray gun or wand, reducing kinks and enhancing maneuverability.

Materials Used in Fittings

1. Brass

   • Composition: Zinc and copper alloy.
   • Pros: Corrosion-resistant, durable, and more affordable than stainless steel.
   • Cons: Less resistant to corrosion compared to stainless steel.

2. Stainless Steel

   • Composition: Coated with chromium for rust resistance.
   • Pros: Highly durable, corrosion-resistant, and chemically resistant.
   • Cons: More expensive.

3. Plastic

   • Pros: Inexpensive and lightweight.
   • Cons: Prone to cracking and less durable than metal options.

Rubber O-Rings

• Function: Prevent leaks in female fittings by sealing the connection between male and female parts.

Pressure Washer Quick Connect Sizes

Choosing the correct size is crucial. Common sizes include 3/8”, 22mm, and 14mm. The British and American standards (NPT and BSP) differ, so ensure compatibility:

• NPT (National Pipe Thread): U.S. standard for screw threads.
• BSP (British Standard Pipe): British standard for screw threads.

For accurate sizing, use calipers. For example:

• M22 Adapter Size: Common on hoses, spray guns, and pumps. It measures 22mm outside diameter and 14mm inside diameter for gas pressure washers. Electric pressure washers may have a 15mm diameter.

• BSP Thread Size: A 3/8” fitting has an actual diameter of around 16.66mm.

• QC Plug and Socket Size: Typically 3/8”, simplifying the measurement process.

Practical Examples

1. Quick Connect Fittings

   • Convert an M22 hose connection to a quick connect with a male thread to female 3/8″ quick connect socket, and attach a fitting with a male quick connect plug to the pump outlet.

2. Dual M22 Male Coupling

   • Connect two M22 female hose ends to extend the hose length without moving the pressure washer.

3. Hose to Spray Gun Quick Connect

   • Use 3/8 inch QC couplings for quick attachment and removal at the spray gun end.

4. Pressure Gauge Integration

   • Insert a pressure gauge with quick connect fittings between the spray gun and hose to measure pressure accurately.