PSI and GPM, Surface Cleaner Ratings, Hose Considerations

Hi Everyone. First Post. Thanks for the add. And 4 newbie questions right off the bat:

Firstly, I’m getting started and got a 4400 psi machine at 4 gpm. I’ve been led to believe the 4400 psi rating is generated by the red tip and the red tip is garbage and should never be used (I’m totally fine with that BTW). So if my machine is rated at 4400 PSI when using a single red tip and the surface cleaner I’m considering is rated at 4000 psi utilizing two 25 degree nozzles, I shouldn’t have to reduce the pressure of the machine to accommodate the surface cleaner; correct?

Secondly, will reducing the PSI of the machine also reduce the GPM output?

Thirdly, is there a rule of thumb about hoses and the rated PSI of the machine? “When buying additional hoses they should always be _____ PSI over the capacity of the machine”.

Finally, for those with 150+ feet of hose, do you have a 100 ft hose + another 50 ft hose, or do you have 3 lengths of 50 ft hose.

I know I shotgunned a lot of questions right out of the gate and I truly appreciate any, and all information I can get. Thanks so much and have a great day.

Welcome to the forum. You have a lot to learn, don’t worry we were all in the same spot at some point. The good thing is that there is a massive amount of information on here, so much that you can read for months on end and still not have read every post.

We are trying to be better about not saying “Use the search bar” as much anymore, because it’s not very welcoming. People that stick around sometimes pay for a membership, and that keeps the lights on around here.

At the same time, not many of the professionals on here have the time or energy to reply to questions that have been answered exhaustively, when the person asking could pretty quickly just click the magnifying glass by their avatar. By digging through the information, you’ll learn everything you need to grow your business and be successful. Things you didn’t even know you didn’t know.

  1. Pressure is changed by changing the nozzle’s orifice size. Bigger holes = less pressure. Search term: nozzle chart
  2. Your pump is always going to put out the same GPM all the way up to the pressure rating of the pump. You can bring it down to 100psi and it’s going to put out 4gpm. Same thing with 3000psi, still 4gpm. Search Terms: gpm, softwash, psi
  3. Not really.
  4. I wish I’d bought 200 continuous feet instead of two 100’ sections. The lump on my reel annoys me, and I’m sure it adds stress at the connection. Search term: continuous hose

I have 200 ft but got a 150 ft and a 50. Most blowouts happen close to the end of the line so this way I can just swap out a 50 ft instead of replacing the whole hose

The 4400 psi is the pressure it will build up to internally before shutting off/diverting the pump, so if you aren’t on the trigger the pump will run until it hits max psi then stop

To clarify, the pump never “shuts off”. It just recirculates the water instead of pushing it out of the gun. I don’t think @Bigbendwashpros meant to give you the impression that the pump stops pumping when you’re off the gun, it was just worded like that.

If you put a tip on there that would create 5000 psi, your unloader would think you were off the gun and start recirculating the water internally.

All this talk of 4400 psi makes me nervous, definitely do some research on here about safe pressures on siding, wood, concrete, etc. It’s all way below 4400PSI, often down to 80-100 psi


Yes Jake is right. Was trying to make it easy for him to understand but should have been more clear