Vegetable Oil Heating Revisited Part 2

I built a veggi oil pump with a used sump pump from a Ford 460 engine driven by a windshield wiper motor. I had a heat exchanger set up on a diesel generator to keep the oil warm. It just recirculated the oil past the fuel valve of the generator, through the heat exchanger, and back to the tank. The hardest part of building it was my windshield wiper motor turned the wrong way so I had to stick a differencial from a lawn tractor in to reverse the rotation.

I have heard of using windshield wiper motors to drive the oil pump, for my use I found a stepper more precise, and also allows me to adjust the torque independent from the speed.

Your project sounds interesting, would you like to take some pictures and a short write up about, and we can post it as a project here?

Been following your blog entries here, and am in process of setting up my own system. I hope you can save me some time shopping. where did you purchase the little pin heater, and do you know where i might find a tube heater?( hollow large enough to run a 1/8" pipe thread iron pipe thru?)

Thanks, Mike

623@telus.net

Frank, I am in the process of designing a setup simuliar to yours. I will be attempting to do this without modifying the pump. I will be heating the oil prior to firing the burner. I plan to achieve this by adding a delay to the burner/blower while the cartridge heater heats the oil. The cartridge heater will be triggered by the thermostat. My only problem is that the flame detector may shut the burner down before it even attempts to fire. I believe that the detector is set for 45 seconds before it shuts down. I can bypass it but I really prefer not to.

Part 3 of my post describes my temperature controller setup. When their is a request for heat, the temperature controller begins heating the preheater block. When the preheater block gets to 180 deg then it sends a signal to fire the burner. I simply used the alarm output from the temperature controller to send the request to the burner to fire.

If you delay the burner motor then you would only be running the spark and flame eye, I am not sure why you would want to do this. As you point out the flame eye would simply detect a fault and shut the burner off before the oil ever comes on. Bypassing the flame eye is a bad idea as you note.

I don't know if this will be any help to you but the flame eye needs to detect no flame before it turns on the burner, and then it needs to see a flame. What this means is that if you short the flame eye contacts the burner will not fire when heat is requested, until you un short it, and then will run for the set fault time unless it is shorted or sees a flame.

I have tried the approach of using the oil pump as it was, and I found the flame size to be very unstable. It was so unstable that I felt it was quite unsafe, the pump is designed for light oil, unmodified it really does a poor job with vegetable oil. The modified pump has been very reliable and stable so far. The hardest part of modifying the pump was figuring out how it worked, and controlling the speed, but was well worth it.

try using the thermostat to start your oil preheater ( you will need a relay switch), and a second circuit for the pump motor, and igniters with a disk switch near to the temp of the oil that you require.(160-190F) a further sugestion is to use a tube heater around the fuel tube directly behind the igniter mounts to keep the oil heated during off time. result, no thick cold oil at fire up

Frank, when you say you tried to use the pump as it was, do you mean without the heating element on the nozzle block? I was thinking of preheating before the pump, and using delay valve so I wouln't have to bypass any safety features. You mentioned pump presure being on the low side 5 psi. If I was also thinking that with proper temp, higher pump pressure, and a smaller nozzle gpm I would be able to achieve proper atomization. How do you feel about that? Also what gpm nozzle are you using, and what spay angle? Generally Becketts use 80 degree, try anything other than that?

I dig your set up and appreciate your time, thanks for the post.

Jeremy

I am running the pump very slow and using the oil pump more like a dosing pump to deliver a constant flow rate of oil. The oil pump as it was designed is meant to deliver a high pressure of oil, and the nozzle determines the flow and so I had to modify it. I would not try to run the system without heating the oil, it needs to be heated to run, so no this is not what I meant.

The nozzle is a siphon nozzle that takes both air and oil, the one I am using is rated at .5gph but this rating is based on a certain air pressure and oil level. By adjusting the air and oil pump, I can run my .5gph nozzle anywhere from about .2gph to about 1.5gph but those are just guesses based on fuel use. I don't know what the spray angle is, although the nozzle looks similar they are nothing like the standard oil burner nozzles. Siphon nozzles are made by both hago and delavan although neither states what the spray angle is like they do for the standard oil burner nozzle.

I am curious how you are running your furnace? Might you be using a standard style controler? If so what kind of a eye are you using to see the flame? Trying to intrigate a controler into a furnace using a babington ball for an atomizer. It seems that you have a good grib on the handle here.