... 3 easy maintenance and easy installation' 4Full automatic control waste oil boilerModel No.: WOB-10 Features:1.Various fuels are applicable ... , waste grades #1, #3, #4 heating oils, waste mixed heavy oil etc., as well as regular oils, such as diesel, etc ... , etc.3. High back pressure, tubular three-way exhaust and horizontal operation make high burning efficiency. 4. All parts are tested ...