Before revision: Wood-burning water furnaces, boilers and melters The furnace used a forced and induced draft fan to draw combustion air and exhaust gases through the combustion chamber at 1/3 of the speed of sound (100 m/s+).
After revision: Wood-burning water furnaces, boilers and meltersvfd The furnace used a forced and induced draft fan to draw combustion air and exhaust gases through the combustion chamber at 1/3 of the speed of sound (100 m/s+).