how do pressure washers work
How a pressure washer works. Here's a quick summary of the basic principle: 1  Detergent flows in from a bottle or container through one hose. 2  Cold water flows in from a faucet (tap) through another hose and is filtered on the way in.3  An electric motor or diesel engine powers the washer. Cold water flows in from a faucet (tap) through another hose and is filtered on the way in. 2  An electric motor or diesel engine powers the washer. 3  Powered by the engine or motor, a water pump (impeller) draws in the detergent and water and mixes them together.