Cleaning vinyl siding

Yesterday I cleaned a vinyl sided house with hot water. I had my pw set at 3000 psi @180 degrees. I used a 40 tip which is what I use most of the time and I kept the tip about 6 inches away from the siding which is basically the distance I use to clean most houses. My fan pattern was about 2-3inches wide which means the pressure hitting the house is aprox 1000-1500psi.(I learned how to figure the psi hitting the house from this here very informative bb) Anyway by using the hot water I cut my job almost in half because it cleans up so much faster. I didn't even need to use any cleaning chemical for the house except for the gutters where you always need to use cleaning chemicals to get the black lines out. I just wanted to pass this info to you guys/gals to get your thoughts on it and to relay info to help any of you who need it.-John-

John,
I have the same setup as you. I don't use my hot water on vinyl. I use the 40 degree tip as you do and use a good house wash too. With the chem I can keep my tip about 12 inches from the surface and have a 6-8 inch pattern. I feel my pressure at the surface is lower also reducing the amount of water I am pushing up behind the siding. It is fast, clean, and the chem only costs a little over $1.00 per gallon. Cleaned a big 2 story vinyl Saturday morning that was mildewed bad and took less than 4 hours. I used 5 gal of chem on the house injected through my down stream injector. I have tried as you are talking, but I found that I was spending more time (labor) and more fuel (expense). I have found that this chem earns its keep.
Glenn

What is the chemical you use?
Thanks!

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