As requested here is a more in depth explanation about the benefits of using purified water to rinse a car that is being valeted.
Firstly it's worth mentioning that this isn't a new idea. Valeters in the USA use purified water as standard practice just as most window cleaners in the UK do.
Purified water evaperates without leaving marks on the paint caused by all the contaminents that is in tap water, so there is no need to blade and then wipe the excess water from the vehicle, you can simply leave it to dry.
This means if you are working outside on a hot sunny day, there is no need to rush around and struggle to keep the vehicle wet until you are ready to dry it, you can simply wash a section at a time, sprinkle with purified water and forget it.
If you are cleaning several vehicles and pushed for time, you save time by not needing to dry any of the vehicles. After washing each one and rinsing it you can move on to the next.
The drive through guys also benefit because they can just wash cars and send them on their way knowing that any water running out of anywhere will dry streak free.
You get a glossier finish by leaving to dry naturally because as you don't rub the car dry, you don't create streaks in the wax.
Purified water is also really good for cleaning the glass, inside and out.
A microfibre dampened with purified water is excellent for cleaning all the glass, just wipe over and leave. You get no smears, no struggling with liquid glass cleaner drying before you have had time to buff it off and no dust from glass polish. So as well as making life easier it also saves on chemical costs.
The other thing about purified water is that it also cleans really deep.
Purified water really wants to be dirty and contaminated. It acts like a sponge when it's pure, soaking up all the dirt from the surface it's touching. Window cleaners use no detergant at all. The purified water cleans the glass and frames saving the window cleaner time, effort and money. The 1st few cleans don't produce the best results, but after the water has sucked all the dirt from the glass and frame, each clean after that looks great.
Car cleaning is a little different as you do use detergent to clean the vehicle, then tap water through you pressure washer to rinse the detergent away, and then you sprinkle the clean vehicle with purified water to wash away the contaminated tap water instead of drying it.
Step 1, wash the vehicle.
Step 2, rinse the soap off.
Step 3, sprinkle with purified water.
Step 4, allow to dry to a beautiful finish.
I use purified water for my valeting business and have recently set up a company supplieing specially made units for valeters as I personally think it's the best thing to come along for ages.
Hope this is enough information and not too boring.
Thanks
Alan.