Concrete 9 months old

[jdc491]

Hey guys, I am planning to approach a small store owner about cleaning his store front and sidewalks and dumpster pad. Which leads me to my question, the store was remodeled about 9 months ago and some of the sadewalks replaced. The employees drag the trash bags over them to the dumpsters which has caused some pretty dirty sidewalks. With the concrete being so new I am wondering how you guys would recommend I approach the new concrete part of the property? Provided I get the account I planned on doing a few test spots, but say the new concrete can't handle much pressure how would you go about it? If any more info is needed I'll gladly add it in. Should have some pictures of said concrete today.

 

[Timothy]

Hey guys, I am planning to approach a small store owner about cleaning his store front and sidewalks and dumpster pad. Which leads me to my question, the store was remodeled about 9 months ago and some of the sadewalks replaced. The employees drag the trash bags over them to the dumpsters which has caused some pretty dirty sidewalks. With the concrete being so new I am wondering how you guys would recommend I approach the new concrete part of the property? Provided I get the account I planned on doing a few test spots, but say the new concrete can't handle much pressure how would you go about it? If any more info is needed I'll gladly add it in. Should have some pictures of said concrete today.

I would wash new concrete the same way I wash brick pavers. The correct detergent blend to break down the contaminates and then 8 gpm at under 1k psi. Sometimes we are under 600 psi.

 

[jdc491]

Thanks for the input. What tips are you using to put yourself in the 600 psi range? I'm running 8 gpm at 3500 psi

 

[Timothy]

Thanks for the input. What tips are you using to put yourself in the 600 psi range? I'm running 8 gpm at 3500 psi

I don't know off hand. I have a pressure gauge at the surface cleaner and sometimes just turn down the ball valve to drop pressure.

When in doubt, consult a nozzle chart.

 

[Paul Kassander]

Great use of the nozzle chart Tim.

 

[snagtooth]

So kind of a hijack but pertaining to using nozzles to change pressures. You can always lower pressure with bigger orifices but is there a general rule for safely raising pressure using smaller orifice? As in, how much can you raise pressure without causing damage to components in your system (pump, etc.).

 

[pinpointdan]

When is concrete no longer new

 

[Russ Johnson]

So kind of a hijack but pertaining to using nozzles to change pressures. You can always lower pressure with bigger orifices but is there a general rule for safely raising pressure using smaller orifice? As in, how much can you raise pressure without causing damage to components in your system (pump, etc.).

Do not raise pressure past the manufacturer's rating.

 

[Paul Kassander]

also if your unloader is set properly no matter how small you go on the nozzle your pressure won't change beyond the setting ie. 3500psi. you will just reduce the flow rate on trapped pressure unloders.

 

[pinpointdan]

Paul, would you elaborate?

 

[Russ Johnson]

you will just reduce the flow rate on trapped pressure unloders.

...and drive a flow controlled unloader berserk...

 

[Russ Johnson]

Paul, would you elaborate?

That machine has a regulating unloader on it, set at 3,500 psi. No matter what nozzle you put in it, it won't go higher than 3,500 psi. It will cut back on the water flow, and dump what you aren't using back in to the tank.