A syphon burner can run on almost liquid fuel you can find including: used cooking oil uco, svo or wvo, used motor oil umo or wmo, used transmission fluid, used gear oil, etc. It’s even able to run on regular old home heating oil if your waste oil supply runs low. Just turn of the preheater to burn hho. Any used oil needs to filtered before burning or the debris in the oil can clog the nozzle. There are several different ways to filter your oil from simply pouring it through a pair of blue jeans to setting up a centrifuge. Covering all of the methods will need to be covered in a different article. I already have an article on this site about how I filter my wvo for use in my vehicles.
Working on a heating system can be dangerous. Modify your heater at your own risk. Do not try to service a heater if you do not know what you are doing. You can be injured or start a fire.
After using a waste oil pressure conversion for 1 season I wanted to upgrade to a syphon conversion. Since a syphon conversion is made up of three basic parts, this article is one of a three part series that covers the syphon burner, constant level tank and the air compressor.
See the other parts of this series of articles by clicking on my screen name or visiting my blog.
A syphon burner works like an air powered paint sprayer that a body shop would use. The air is forced through the spray can where the paint is drawn up the feed tube and broken into small droplets as it exits the spray nozzle. Portable “torpedo” heaters use this principle. There is a Yahoo group called Altfuelfurnace that has all of the details on converting a standard home heating oil burner to run on waste oil. Craig from CK Burners makes a nice conversion kit. The sell everything from basic parts to complete kits with excellent instructions. I don’t get anything from recommending his kits, I’m just a satisfied customer. See www.CKburners.com for more information. Craig has a very informative site with lots of photos, part numbers and links to where you get the parts needed to build your burner. He has started offering hands on workshops were everyone goes home with a working burner. It gives a beginner a big head start.
You will need an oil fired furnace or boiler to burn waste oil. If you have gas heat you’re not out of luck. Some guys have installed an oil fired boiler and added a heat exchanger to their existing furnace. The fan in the furnace blows air through the heat exchanger where it is warmed and sent through out the house, much like central air conditioning works. An oil fired boiler can be piped into a system with a gas fired boiler. Some guys like to install the waste oil burner in an out building to avoid insurance issues. Hot water can be piped into the house with buried pex tubing the same way it’s done for large outdoor wood boilers. These situations are more complicated, but it can and has been done. I have a Tarm dual fuel gasifier boiler. It can burn wood or home heating oil and now waste oil. It’s plumbed in with a Munchkin 96% EFU natural gas fired boiler. I can get hot water from a coil in the Tarm boiler or from a wall hung on demand water heater in the summer. I can heat my home with every fuel source except coal!. I will publish an complete article about my heating system soon.
If you already have oil heat you’re half way there. It’s recommended that you acquire a second burner to modify and leave your existing burn as a back up. Most oil guns can be converted to waste oil. They just need to have a 4″ blast tube if you are going to use a kit from CK Burners. The Beckette AF and AFG guns are the most common burners to use because there are plenty of them available and most parts are interchangeable. There are new motors and high voltage transformer available today. The older ones work fine, but the new style parts use a little less energy and the transformers produce a higher voltage which provides a “hotter” spark to the fuel.
Syphon Burner Parts description:
The electronic controller that holds the heater block at a preset temperature and tells the primary control to start the burner.
Heated nozzle block
The CNC machined part that takes the place of the J-tube in a conventional burner. It holds the heater element, electrodes and nozzle. It preheats the fuel and air to the nozzle.
The 4″ metal pipe that covers the heater block and connects the burner body to the heater.
The flange that fits over the blast tube and bolts to the heater. It adjusts to set how deep the burn goes into the firebox.
Flame retention head
The finned part that fits on the end of the blast tube. It helps to swirl the combustion air with the fuel to aid with burning the fuel.
The PID is not able to handle the amount power to run the heater element. A 110v relay is needed to switch the heater element off and on.
The rest of the components are common oil burner parts and don’t require a description.
If your not familiar with servicing your heater you can find articles and YouTube videos to show you how. Residential Oil Burners by Herb Weinberger is a very in-depth book that’s written in an easy to understand language. Once you have your burner and conversion parts you’ll need to completely disassemble your burner and clean it. An automotive parts cleaner and a cheap paint brush make short work of the cleaning.
The key component in a syphon burner is the heated nozzle block. It comes machined with passages for the air and fuel. The heater cartridge fits into the middle of the nozzle block. It has a tapped port for the thermocouple and a bar to help hold the nozzle centered in the blast tube. The stock J tube needs to be shortened, threaded and screwed into the back of the nozzle block. Instead of supply fuel like it would in a stock burner, it now supplies the atomizing air to the nozzle. The fuel feed tube screws into the rear of the block with a 90 degree NPT fitting. It exits the blast tube through the pre-drilled hole where it can be connected to you constant level tank. The nozzle block with shortened J tube are longer than most stock J tubes and blast tubes. Most conversions will need a longer blast tube. Some older Beckette burners did have very long blast tubes, especially the old wood/coal to oil conversions. If you need a new blast tube Craig suggests a section of 4″ exhaust pipe. An adjustable blast tube flange allows you to adjust how deep your new burner will fit into the fire box. Beckette recommends that the flame head should be flush with the insulation on the walls of the fire box. Many guys using a waste oil burner find that inserting the burner an inch or so deeper into the fire box can reflect more heat to the flame head and help reduce carbon build up on the flame head.
The PID is the brain of the waste oil conversion. When the burner get a call for heat the PID will activate the relay and turn on the heater element. The nozzle block warms up and the thermocouple reports the temperature back to the PID. When the block is up to your preset temperature the PID will active the primary control. The primary is wired to power the high voltage transformer, the burner motor and the air valve. The fan on the motor supplies the combustion air, the atomizing air will draw the waste oil through the fuel tube and out of the nozzle where the high voltage spark will ignite the fuel. If the cad eye “sees” the fire the primary will continue running the burner until the call for heat ends. In some burner you may need to move the cad cell closer to the blast tube so it see the fire. My syphon burners did not require the cad eye to be moved, but I had to relocate it in my pressure burner.
Craig supplies easy to follow instruction with plenty of photos if you purchase you parts from him. The kit comes with the blast tube pre-drilled for the fuel feed tube. Last year while using my pressure conversion, I found it very convenient to be able to remove the blast tube to access the heater block, electrodes and nozzle. I didn’t want have to unscrew the fuel tube every time I needed to service the heater so I notched the blast tube to form a slot for the feed tube instead just the hole (see photo). I also added an adjustable snap disk limit switch to the heater block to prevent it from over heating if the PID or the relay ever fail. Craig recommends setting the heater block to be 180 degrees. I set my limit switch at 210 degrees. I used stainless steel welding wire to attache the limit switch to the heater block. I didn’t want to drill into the heater block and risk hitting the air or fuel passages. I wired it into the hot wire between the relay and the heater element. It provides an easy to way to disconnect the power to the heating element if I want to run HHO or service the burner without the need to remove the primary control and dig into the crowded electrical box.
At this time my system is up and running flawlessly. I’m using free, salvaged refrigerator compressors to supply the air and an old ammo can as a constant level tank. The burner has not required any cleaning so far.