If you’re a value shopper like me, you’re looking for the most bang for your buck. So you open your tabs and (if you’re really obsessed) your spreadsheets and start comparing. However, everything isn’t always as it seems. 18V isn’t any different than 20V max. There’s no good comparison between in-lbs of torque and unit watts out. Then there’s pressure washer PSI and PSI max.
Certifying Pressure Washer PSI and GPM
In today’s world where it’s hard to know who to trust, objective testing and data are worth their weight in gold for people who want the honest truth. When it comes to shopping for pressure washers, certified PSI and GPM ratings from PWMA (Pressure Washer Manufacturer’s Association) and CETA (Cleaning Equipment Trade Association) are very important because they tell you what you can expect when you’re actually working.
That seems like kind of a “duh” statement, and until a few years ago, I wouldn’t have thought it worth writing an article about. But that was before the term “PSI Max” and “GPM Max” started showing up on brands such as Sun Joe. It’s a measurement that tells you the highest momentary pressure you can get. The upside is you have an idea of the greatest injury/damage potential. The downside is that it’s usually way off from the working pressure.
Pressure Washer PSI Case Study
Take Sun Joe’s extremely popular SPX3000. It’s a 14.5-amp electric pressure washer that boldly claims 2030 PSI Max* with 1.76 GPM Max* and runs $169 for the pressure washer alone. To get similar numbers from Greenworks or Ryobi, the best you can do is $199 and you’re still short by more than 0.5 GPM.
But scroll down the page (or check the fine print on the box) and we find the working ratings. For the SPX3000, you actually get 1450 PSI and 1.24 GPM of cleaning power. That’s 28.6% lower PSI and 29.5% lower GPM from the Max ratings. If you assumed the PSI Max and GPM Max ratings matched up with other competitors, the performance difference would be disappointing.
The potential for these Max* numbers to be misleading triggered changes based on Better Business Bureau findings.
PWMA-Certified Pressure Washers Vs Non-Certified
|PSI Max||NA||NA||2030 PSI Max|
|Working PSI||2000 PSI||2000 PSI||1450 PSI|
|GPM Max||NA||NA||1.76 GPM Max|
|Working GPM||1.2 GPM||1.2 GPM||1.24 GPM|
The Bottom Line
The main point in all of this is that if you’re seeing pressure washer PSI numbers that seem too good to be true for the price, it probably is. Going with a PWMA-certified pressure washer carries with it the confidence that the ratings the unit claims are what you can expect to get when you’re pressure cleaning.