concrete & awning

[hydro-clean]

I have to do a tgi fridays theey have red and white vinyl awnings and real dirty concrete. it hasnt been cleaned for over a year i ordered awning cleaner, hopefully that works, but i need a way to really brighten the concrete i did a test spot and alot of dirt came off but when it dried it still looked dirty. any suggestions on both the awnings and concrete? thanks, i have a 3000 psi@4.5gpm hot water machine.

 

[ron p]

ron p

for cement you can try oxalic acid [used by meny deck washers]
you could use a weak muratic acid solution.
either should never be used where the waste water is allowed to run into a storm drain.