I would say if you already have a pressure washing business, then adding hoods would be pretty simple. You have the equipment, all you really need is a way to apply chemicals and rinse them off on regularly maintained accounts. Scraping would be required on first service accounts only if you are doing the job right.
If you would like to get more information on our industry, there are a few websites that you can visit to obtain more information. There is a great free kitchen exhaust cleaning manual here:
IKECA Kitchen Grease Exhaust Cleaning Manual
And this bulletin board as well as
Pressure Washing Institute Power Wash Network - powered by vBulletin and
The Grease Police Forums all have great information on kitchen exhaust cleaning.
If you get serious about it, your next step would be to become certified.
Once you get in to it, you will see that having the right knowledge, tools and chemicals, just like in any other cleaning industry, is priceless.Right now we are down to applying chemicals with a foamer, and rinsing with a water hose on most accounts. We have sold all of our large pressure washing equipment, and our jobs are getting easier and easier (read more profitable) each day.
I see the kitchen exhaust cleaning industry moving farther and farther away from the pressure washing industry in the future, but that does not mean you should not or could not pressure wash an exhaust system. Get your feet wet with the tools that you have and see if it is right for you. If you like it talk to some different guys on the boards and see if they have some suggestions on making it easier.
Here is an example of a charbroiler system that was cleaned with nothing but a foamer and a water hose, can't get any easier than that.
