I prefer to use acid cleaner first like viper renew, or tog easy etch (make sure you have no reaction to the actual tile as you don't want to etch the tile as in stone). I just spray the grout lines and let dwell about 10-15 minutes...then scrub your grout lines with a stand up brush. However if the floor has a lot of grease and you don't get any foam you need to start with an alkaline product. Like viper venom, or tog deep clean scrub with your blue brush. Give the chemicals time and scrub.
3 Rinse your floor....high pressure is not necesarry. You just want to suck it all up and make sure you leave no residue....same as with carpet.
4. Precondition again with alkaline to clean your tile surface. If you had to use alkaline an acid wash is the next step. Scrub (175 is best here to get the tile surface clean if it's real bad) and rinse again. If you use acid this step it's recommended to spray alkaline out and dwell again in another step to leave your grout in an alkaline state....as that's it's normal state.
So... You go in, put down your acid(which doesn't clean it etches). Then you find the acid didn't get to the grout in places because of soil. So now you clean up the acid to clean with alk to get rid of the soil so the acid can etch the grout. Then you acid treat again to get the splotches and areas that the acid didn't get before. Now you put down more alk to neutralize the acid that the grout itself has already neutralized........ Maybe it's me but it sounds complicated and what 3-4 too many steps.
I went through this on another board with a guy who thought he came up with some new exciting way to clean grout just like you. You can get away with your method in many resi situations, so have at it.
It's the right way to do it and you know it.
And btw it's not complicated at all....it's called understanding what you're doing and when to do what you're supposed to do.
I will venture to say I know slightly more about grout, it's chemical properties, uses, weaknesses, etc than you. I have enough college chem courses to be a little dangerous. I will say with certainty, that with the acid products that I use, (taking into account their ionization values, and dilutions) I am pretty much wasting my time neutralizing after the grout has already done so. You see, when the fizz stops, so does the reaction.
And yes I know grout is alkaline by nature, it has a PH of 12-14 when it is initially mixed. After hydration the ph would be 8-9 if you got it wet.
Now I prefer to simply clean with an alk first, to get rid of all the acid blocking soils, and treat it with an acid product after if needed, than risk the above cluster mess.
But if it works for you, git er done.
