I was in the chimney business for 20 years took the Boiler Service course at Boces and work a little on boilers and I always wondered why the oil tech servicing the boiler did not sweep the oil flue. It is because he did not have the right tool, THE HANDY VIPER. Some flues are easy and others difficult for some reason.. With the Handy Viper just do the easy ones, EASY n SWEET. If it is difficult for some reason have them call a chimney sweep. But if it is easy and easily accessible, you are there, the flue is right there and you now have the right tool the HANDY VIPER, so why not you do it and make extra $$ It is maintenance and you want the entire system clean not just part of the system. Also addition income with little expenses means PROFITS. We all love PROFITS. This tool will pay for itself very quickly as you will see. If you have the right tool you can make money.