Why PSI and BAR Confusion Costs Money
If you have ever imported a pressure washer, bought European equipment like a Kranzle or Kärcher Professional, or bought aftermarket pump parts online, you know the headache. North American manufacturers rate pumps in PSI (pounds per square inch). European and Asian manufacturers rate them in BAR (1 bar ≈ atmospheric pressure at sea level).
• BAR = PSI × 0.0689476 (or divide PSI by 14.5038)
• PSI = BAR × 14.5038
Watch Out for the "Peak vs. Working Pressure" Trap
In Europe, pressure washing manufacturers are legally required to test and publish their machine's operating working pressure. If a Kranzle box says 140 BAR, that pump puts out a solid, continuous 2,030 PSI while you hold the trigger.
In North America, consumer-grade electric brands often pull a marketing trick: they slap the spike pressure on the box. That is the brief microsecond pressure spike recorded the instant you let go of the trigger and the unloader shuts. A box that screams "3,000 PSI MAX" might only run at 1,800 working PSI (124 BAR).
When you convert BAR to PSI, always check whether you are converting real continuous pump working pressure or momentary spike rating.
Pressure Without Flow Is Meaningless
High pressure cuts and lifts grime, but water volume (GPM or LPM) is what actually pushes grit away. A 2,000 PSI machine pushing 1.2 GPM (82.7 BAR at 4.5 LPM) will clean at a crawl compared to a 2,000 PSI machine pushing 4.0 GPM (15.1 LPM). Convert your machine's volume with our LPM to GPM Flow Converter.
Once you know your operating pressure in PSI, you must match it to the right nozzle orifice. Putting too small a nozzle on a high-flow machine will bottleneck the pump, spike your line pressure past the safety unloader limit, and blow out your hose fittings.
