As an automotive repair shop we generate a lot of used engine oil, transmission fluid, brake fluid, gear oil, old gasoline and diesel fuel. The best way to dispose of this hazardous waste is to use it as a heating source for the shop. The furnace is a clean burn just one of many available to shop owners for heating the shop. One would think that it would have an oil smell coming out of the exhaust stack, but it doesn't. It burns so clean that there is no smell or smoke. The furnace is equipped with a filtering system that filters the oil before it is burned. As you can see we developed our own per-filtering system to insure our storage tanks do not get contaminated. All the used oil is put in the 55 gallon tank and pumped through the inline filters into the storage tanks. The furnace has been in use for several years and the furnace filter has never required service. The burn chamber requires service once a year. About every two ~ three years a major service is required by the supplier. This has been done once and when the service person came out he said this was the cleanest one he has ever serviced. It pays to go the extra mile with maintaining equipment.