Stainless steel heat exchanger and flue tubes prevent rust and increase the life of the furnace. Heat exchanger and flue tubes are designed to limit heat escape and maximize the heat produced. Flue tubes are swedged, not welded, to resist cracking over years of heavy use. Cleanout is easy, and with longer service intervals of 1,000+ hours, less frequent. Over center latches allow easy cleanout without tools. Digital, programmable burner control for reliable operation in all conditions. Thermostatically-controlled pre-heater easily pass UL cold oil start tests. Burns a variety of fuels including most synthetic oil, and just about any mixture of oil products. Includes a pre-assembled, vacuum-tested metering pump that does not require user adjustment. Easy access oil line connector block allows servicing without disconnecting the oil line. Extensive support network with local representatives from coast to coast, as well as factory support.