Repair Guide

Pressure Washer water connections for water inlet and water outlet

The basics

Your pressure washer water inlet is almost always larger in diameter than your outlet connection.

Water In

Water Inlets are generally 3/4 inch BSP and measure 25mm in diameter approx.Some larger Industrial Pressure washers from the Karcher brand have 1 inch BSP water inlets that measure approx 30mm in diameter.

Example of some common water connections :

• Left - Claw fitting known as GEKA
• Middle - Garden style fitting made popular by gardena and hozelock (also available in brass)
• Right - Click-on fittings with ball bearings inside are made in many slight variations but KEW use NITO

The inlet thread usually has some kind off click-on coupler to allow a tool-free connection to the water supply hose. The most common connector is the plastic garden coupler from brands such as Hozelock or Gardena. KEW pressure washers chose the NITO brand for the durable industrial metal quick connectors. Some people like to use the claw fitting too.

Water Out

Most power washers have a threaded water outlet and the common thread type is M22. Metric M22 is used by Karcher MAC Powerbase Champion and more although the internal bore of the connect maybe 14 or 15mm in diameter. Nilfisk Alto KEW use an imperial 1/2 inch BSP thread, on the domestic range, that is very difficult to differentiate from the common M22 thread. WAP use M24 and M28 metric threads with the machine thread being female rather than male.

See our other Blog - How to Identify your thread