The Thermo Pride OL5-85RB furnace was installed in this antique farm house in September, 1996. At that time, it was a largely state-of-the art, warm air, oil-fired furnace of a type commonly found throughout New England. At the time of installation it achieved an 85% burning efficiency. The furnace consists of a large, steel cabinet in one end of which is a nearly four foot high, cast iron tank-like device which is the burning chamber. In the bottom of this “tower” like thing is set an oil “gun” burner (Carlin brand) which shoots an oil stream into the chamber and ignites it. The resulting air from the combustion of oil is then blown through 8″ and 10″ galvanized steel conduits to outlets located in rooms on the first floor of this house. When the furnace was first installed (by a previous owner of this house), the heat needs of the house were augmented by a wood stove which exhausted smoke through an exterior chimney. At the time of our occupancy, the chimney and wood stove were removed, and we found the Thermo Pride furnace to be more than adequate for our heating needs in that late spring as we began to repaint the interior of the house. However, several other issues with the heating system were discovered. First of all, some of the warm air ductwork was loose or had actually separated from registers in the most remote areas of the house. These areas were in crawl spaces and repair of the ductwork was difficult. Furthermore, this ductwork was in unheated areas and not insulated. The resulting heat loss in deep winter would have made the otherwise good heating efficiency of the Thermo Pride furnace irrelevant as only by driving the furnace hard on those long, very cold winter nights could real warmth be maintained throughout the house. Warm air in circulated by a very large fan system driven by a powerful electric motor. Considering the house is approximately fifty feet long, this fan must be very powerful and the resulting electrical consumption plus the oil needed to provide heat indicated a very expensive heating system at the time we moved into this house. What was a highly efficient and quite expensive furnace and heating system in 1996 was obviously totally obsolete less than twenty years later. Immediately I began a complete heating system retrofit. The Thermo Pride furnace was shut down once the existing supply of fuel oil was depleted. I installed three Toyotomi computerized wall furnaces in different locations in the house. These small wall furnaces develop 20,000, and 8000 BTU’s specifically, burning either kerosene or ultra-low sulfur diesel fuel, and are fed from a single, 275 gallon exterior mounted fuel tank, through a single, electric distribution pump. Now in the fourth year, the system works well, the house is warm in the coldest periods and the fuel consumption through the year is approximately one quarter what the old furnace consumed. I have also added a considerable amount of insulation, particularly beneath the first floor, and blocked off all the old warm air registers. The fuel burned by the Thermo Pride is still the lowest cost, highest BTU fuel available for heating, and if the Thermo Pride furnace was located in a modern house with a full, insulated basement that was not as spread out as this house is, it probably would still provide excellent heat and relatively manageable fuel use and value. But for this house its time has passed and I cannot rate it highly in this particular application.