At what point do you need chemicals?

[chechnya]

Hi there.

So when i buy my rig im considering maybe a 5000psi, 8+GPM rig. At what point is the pressure not enough to remove things like paint from brick, graffiti, etc? The only experience i have with a pressure washer was with a 2600 PSI(not sure of the GPM) cold water stand alone unit. It really got rid of alot of nasty stuff from flatwork like my driveway and sidewalk. But when does just pressure alone become ineffective by itself?

I forgot to include im mostly talking about a hot water unit 200F-220F.

 

[Larry B]

2600psi is more than enough in most cases. The idea behind using chems is less pressure and more rinsing the dirt off. 5000 psi will ruin a lot of surfaces.

 

[chechnya]

I used to supervise this newbie doing crap jobs so i made him pressure wash. When i came back, he etched into the concrete. Ohwell i guess. My fault.

Im just worried that a 4000PSI 5-9GPM hot unit wouldnt be enough to remove graffiti and thats why people use chemicals. In what cases would you HAVE to use chemicals? Roofing? Red spray paint?

 

[FCPWLLC]

In our business, Chemicals are our friends. Chemicals allow you to work faster and smarter. The use of chemicals help to insure that we are not using too much damaging pressure. Graffiti almost always requires chemicals. Vinyl Siding Cleaning should always use chems versus pressure. Wood cleaning shoul be done with chems and NO pressure.

The Hood cleaning guys use chems... All of us use chems versus pressure.

 

[chechnya]

In our business, Chemicals are our friends. Chemicals allow you to work faster and smarter. The use of chemicals help to insure that we are not using too much damaging pressure. Graffiti almost always requires chemicals. Vinyl Siding Cleaning should always use chems versus pressure. Wood cleaning shoul be done with chems and NO pressure.

The Hood cleaning guys use chems... All of us use chems versus pressure.

Ive pressure washed a wood deck and everything seemed fine? All of the choices are overwhelming so i just need to compile a list of whats what, order a small batch and test.

 

[FCPWLLC]

Sodium Hypochlorite will be your chem of choice for mold and midew on vinyl, concrete etc... On my website, you will see a link for a great deck cleaner. try it. Mark can also help you with some sample chems to try. Trust me, you should NEVER use high pressure on wood.

 

[grizzley]

Chemicals chemicals chemicals..... then wash. Allot of times, if you use the right chemicals, you can use a garden hose to clean and don't even need a pressure washer.