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Bob, here is a discussion I wrote about my search for a USED oil furnace (its not technically waste oil, but rather USED oil, according to the US EPA). This discussion is not complete but might lead you to look at some of the units I have considered. It is not finished, a work in progress, and I still don't have a good handle on what size heater I need, but I suspect that 250,000 BTU will do me fine. After reviewing the different models and looking at features and calling some of the makers of them, I am realling leaning toward the Omni units, my only hesitation being that they are a pushy bunch of people, like used car salesman, who know theirs is best and everyone elses is junk. I just want the product and don't want to hear all the BS from a salesman. My only real suggestion is that you don't consider one without an air compressor of its own. Being dependent on your shop compressor is probably not a good thing, the air consumption is not huge, but it must be on and working anytime the heater is turned on. Charles..... ... Read on for my "prepared" discussion, any comments or additons? I've started getting serious about doing research leading up to purchasing a whole shop heater. This is for an existing structure so it will have to be a forced air system, no floor heat, and I want a used/waste oil fired system. I'm located in West Central Georgia and in general, the temps usually never go below +15F, though they will often stay in the mid 30's all day in the winter. The building is a 60x60 metal building, with 16 foot eaves and a 12/2 roof. That makes it 66,600 cubic feet of interior volume. Its on a concrete slab and has the vinyl backed fiberglass insulation common to metal buildings, put on before the sheet metal goes up. Its aprox a R7 insulation value. I have one 10x10 metal sheet roll up door and have a lot of air intrusion above it, and I have a 12wx14h metal and glass garage door (no insulation) and experience air leakage around it also. This is an aircraft hangar (but it has a '53 Jubilee and a '67 2000 in it so this is tractor related) and I have a set of doors covering a 14h x 56w opening that are covered in translucent smoke fiberglass sheet (no insulation of course). There are two man doors with glass in the top half of them, and two sidewall skylights about 3w x 9h each. This shop and hangar is not used full time, so a used oil heater would be the ideal method to heat. I myself generate a modest amount of oil for two vehicles and a mower and the tractors and I have a couple of neighbors who change their own oil and maintain airplanes and would be able to give me their used/waste oil. I also have co-workers who change their oil and could just as easily bring me their oil as take it to the auto parts store for disposal. EPA regulations allow me to burn all of the used oil I myself generate and that oil given to me by do-it-yourselfers. I cannot burn oil from commercial businesses without first having it tested (very expensive). I have to burn the oil to produce heat, power or other useful product, and not just to waste it or dispose of it, and the individual heaters cannot exceed 500,000 BTUs each. Those are all EPA rules. When I want the hangar/shop heated, I would want to be able to, within 30 to 45 minutes or so, raise the temp from an unheated condition to near shirt sleeve conditions. This is a situation such as coming home from work and firing up the heat and getting started at whatever I planned to do, or on an off day, turning it on in the morning and having it ready to use fairly quickly. This would mandate a somewhat larger than normal heater. Too large and the frequent cycles become a problem, along with the increased fuel burn. A heater that is started frequently would be more prone to problems and forming of soot and ash and from the poor combustion associated with starting up and shutting down. In looking at heaters I found the following manufacturers. Reznor, which is an old manufacturer of heaters, now owned by Thomas & Betts and who decline to post the location of their headquarters or manufacturing facilities.
Link Firelake, Mt. Crawford, VA
Link EnergyLogic, Nashville, TN
Link Heatwave which is also found under the name Siebring Manufacturing, George, IA
Link Clean Burn, Leola, PA
Link Lanair, Janesville, WI
Link Omni by Econo Heat, Spokane, WA
Link Norki Energy Systems, Poughkeepsie, NY
Link
Sizing selection�
Most of the web sites for these heaters simply list SQUARE feet of building space as a reference for applicable heater size. Generally, they give anything under 5000 sq/ft as being suitable for a 150,000 btu heater. Clean Burn is the only site that has a heater size calculator that takes into account the cubic size of a building or its insulation. Their calculator is very flawed however, giving correction factors that indicate that a no insulation building experiences less heat loss than a minimally insulated building. Also, Clean Burn has a note on the size calculator page that says you must use OUTPUT BTU's when determining desired heater size, then they turn right around and list their different model furnace units and what do they list for capacity? Why, INPUT BTU's of course!!!! Then they note that if you use input BTUs to size the heater, you could end up with an undersized heater. They do have some good information however, such as suggesting the use of ceiling fans in areas which are over 14 ft high. I may very well consider doing this when I wire conduit for the overhead lighting. I searched the web over and have been unable to find a good heat sizing calculator, except for a couple that are specifically designed for electric heaters and give the answers in watts, and not BTUs. I am presently heating the building occasionally with one Reddy Heater, which is a 90,000 BTU model and is quite noisy in addition to producing smelly fumes and carbon monoxide (CO), which can be deadly. From my experience with this heater, I know that I would need at least twice this much heat to successfully heat this building on cold days. Basic design�. All of the manufacturers listed above make units that are essentially horizontal furnaces. Some are designed as space heaters, using standard blade type fans, and are louvered to distribute the air, while some have squirrel cage fans and louvers but are UL listed as furnaces to use duct work to distribute heat. All of the manufacturers have an option to mount the unit about 8 ft up on supports on top of a rectangular used oil storage tank "workbench" of about 250 gallon capacity. This gives you a place to empty drain pans, and allow filters and emptied oil bottles to drip out. Otherwise, the fuel storage tank and the heater may be separate and the heater mounted from the rafters or purlins and the tank placed elsewhere, so long as the fuel line length between the two does not exceed the manufacturers specifications. Due to the design of the units all use some form of compressed air to propel the fuel out the nozzle into the combustion chamber. Some require external air source, such as your shop air, regulated down to 20 to 40 psi depending on the make, and between 2 and 3 CFM of consumption. Not wanting to have to commit my air system to full time operation for the heater, I think this is not a good idea and basically eliminated units that don't have their own source of compressed air. Units without onboard air compressors are Clean Burn, Firelake, Lanair, and Heatwave/Siebring units. Of course another option would be to install a small compressor capable of delivering the needed air and wiring it to the unit, but this is added cost and hassle. Norki, Omni, EnergyLogic and Reznor all use built in air compressors
Available information and specifications�
Some of the above manufacturers provide a wealth of specifications and information about their units, others provide very little, not even enough to make an educated decision about a purchase of their product.
BTU input and BTU output
CFMs of fan
Temp rise
Fuel consumption.
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