Hey 
I’m assuming we all know that rinsing takes an equal (if not longer) amount of time on large concrete areas, so I wanted to quickly ask - using a white tip 40deg 040 size takes a while to move stuff, to reduce the pressure and increase the flow, which size orifice WHITE tip would flush away better…
Top, middle or bottom? I don’t want to buy them all to test - just for the white tip!
Thanks!
We use ball valves for rinsing. Just watch where you put your hands
Thanks @Kps0410 I don’t have the flow for that.
I have tried in the past - but not much comes out of a 4@4 machine 
Ball valves are not made for choking back water and aren’t safe for use of you have employees or regular insurance audits.
…and the tips? Suggestions?
I don’t have employees. I wouldn’t want them doing it. But it works good for me. Having worked around machinery all my life I’m very watchful where my hands are. I do agree that it’s probably not the safest way though.
I would use a 15 or 25 degree try both and decide which one you like the best
Thanks, but I need to rinse - 15/25 is too narrow. The white tip is the ideal “fan”, but right now I have 4000psi, so I want less psi and more flow.
So the white tip at a bigger orifice than 040 would do this - I was just wanting to know if someone knew how big you can go without losing too much pressure to be functional.
Cheers 
I have a 4/4 setup and I would first recommend a J Rod setup. Get a new (dedicated) gun with a qc and put the J Rod on it. The J Rod will come with two washing nozzles - a low wash and high wash. Either/both of these work very well at rinsing/moving water and dirt from an area or already cleaned area. In close quarters I use the low wash nozzle that is more of a fan spray, and if I need reach or power, I use the higher wash tip.
Worth every penny.
https://www.powerwash.com/jrod-kit-6620.html
I don’t know of any discernible difference in these two, besides price.
Extra Gun:
or
Hope this helps.
The J-Rod Kit for 4 GPM includes:
High Rinse/Low Rinse are what I use from this setup for Rinsing down.
2510 is what I use for decks and some rinsing.
My X Jet nozzle honestly does the best for rinsing though.
The orfice size of the the tip is based off the flow of your machine. So say your using a 4040 tip on a 4gpm/4kpsi machine then you should be getting 4 gpm of flow. If you buy a 4070 tip you are still going to only get 4gpm just at a lower pressure probably around 1500 psi. The only thing that’s going to take less time is buying a higher flow machine like a 8gpm. I do this with a 4gpm now so I know. But you start somewhere before you can upgrade.
@Hdglider thanks for the reply. The 4GPM flow isn’t correct though, it can’t be. I’ll explain…
Yesterday, I was doing a large concrete area with my 20” surface cleaner. With a 4@4 you move pretty slow.
I’ve always used your method - so I have 25020 x 2 nozzles in. This gives me roughly 4000psi (and apparently 4GPM).
However, I decided to try my 25025 nozzles in it and wow! I could walk at a nice pace and no redo work what so ever. I wish I’d have tried this years ago.
The pressure dropped to 3000psi, but the larger orifice of the 25025 MUST have allowed some extra flow that the 25020 restricted.
I’ve used the same 20” SC for years and it’s NEVER performed like this. It’s like night and day. I finished the job over one hour faster.
I get the FACTS, with the 25020’s it SHOULD be 4@4, but all I can go off is what actually happened.
I’m very happy that the SC works at a decent speed now.
This is the reason for my thread today - to see if the same applies using a higher flow nozzle of the same fan.
Yes I tried the same deal. My 18 in surface cleaner( gphammerhead) I swapped to 25025 nozzles as well and stopped wanting to lift off the ground as much. But what you are really doing is lowering the pressure to a safer cleaning pressure for most concrete. What you are probably noticing was striping from using too much pressure. However some pumps with good water supply can push more than what they are rated for( not uncommon but can happen). I usually rinse with a 25045 tip and it rinses better than a 4045 because your spray is less dispersed. To be honest the white tip is sitting next to my red tip cover in dust never really use either because they serve no purpose to me. I usually use the surface cleaner to pushe away sludge every couple passes to help get it in the direction I want when I’m ready to rinse. May work for you. Unfortunately for us 4gpm guys time just has to be on your side. Doesn’t bother me if it takes me a extra hour because of it since I’m not booked.
Hmmm I did try a bucket test last week with the 4GPM and it gave 4.5 so I assumed the flow was increased with the larger nozzles. However, you do make a good point with the excessive pressure making the job harder than it should be. Could be that the lower pressure just made the surface easier to clean and the flow remained the same.
I’ll have to see how it goes this coming week and report back.
4000psi is too much for concrete, I know that, and yes, it can cause striping like a 15deg nozzle would in a SC.
Thanks for the chat 
I pour concrete for a living besides pressure washing so you figure your average driveway is poured with 3500psi mix or sometimes if they cheap out they will use 3000psi mix. By the time water is added to the truck to get the slump they want which is 99% of the time too much water the strength of concrete is now down to a 2500 psi mix. The cream on top
If the concrete will come off easier as the concrete is weakened so hense why most people here will say 2500 psi for residential concrete cleaning is fine. Most commercial is poured with 4000 psi or above and is tested on site from truck so you will be fine.
If you guys have direct drive 4gpm pumps you can always swap your pump with a 5.5gpm gear drive pump down the line. 4 bolts and about $800 and you’re done. Of course you want to be hooked up to a buffer tank…but that’s the “best” way to get more gpm and less psi from your gx390. I usually take 100 ft of hose off from my normal 200 ft so my psi is around 2300-2400 for doing concrete.
Depends on size of your machine. Get the tip that maximizes the flow of your machine. Look at a nozzle chart.
Same here for concrete.
@Racer thanks 
I do know the right nozzle is the right nozzle, end of story - I just can’t figure out why I can walk faster using the same machine and surface cleaner, using over-sized nozzles?
25020 is the correct nozzle to maximize a 4GPM machines flow and psi.
But like I said, it’s the same setup I’ve used for years, yet the SC has NEVER cleaned so fast and well with the 25025’s in.
The only thing I changed was the nozzles (reducing the pressure).
This was on commercial concrete by the way. So higher psi should have done better?
