Is it possible? Combustion chamber size?

[altfuelfurnace]

Buderus boilers are very efficient and are a snap to clean under 10 minutes start to finish. This boiler also has a 32 inch chamber which is very conducive to burning waste oil with very long flames. It is awesome I have had no issues and my flame is about 30 inches. I run a modified Ck burner with a metering  pump rather than a siphon setup with a constant level tank I was never able to get it to work with gravity feeding I needed too many btus of heat for gravity to feed it without running out so I spent 700 dollars on a metering pump and it was the best money I have spent. I know the principle is to spend as little as possible but I have saved 20,000 in three years and to spend a thousand dollars to make it work perfect is well worth it. If I can help feel free to ask everyone here is great about help each other.
Good luck
Joe

[altfuelfurnace]

Joe and others, thanks for the explainations. Could you explain about using a
metering pump instead of a siphon setup. Also, could a metering pump be used
with any boiler? My apologies, but I don't understand what the difference is. I
am learning some key points from you guys. I agree that $700.00 is little to pay
when there is so much to gain. Thank you again.
Richard in Vermont

[altfuelfurnace]

Richard With a siphon nozzle the compressed air will siphon the fuel through
the nozzle. The metering pump is a pump that pumps a small (metered) amount of
fuel through the nozzle. If your system needs 1 gph this pump will pump 1gph.
I built my own metering pump using a J type fuel oil pump (I think any type
would work) coupled to a DC gear motor and a speed controler that I could vary
the speed thus vairing the oil output. Just bench tested this by timing run
time and measuring output. The DC motor I got had a max speed of 100 RPM and my
max output is over 1 GPH. I found the DC motor on e-bay for around $50and the
speed controller was about $50 also, the pump I had from an old burner. So I
don't have much invested but have been very happy with the results. Hope this
helps
Kevin

[altfuelfurnace]

Do you need a solenoid valve stop and start the oil before the nozzle? How exact
on the metering do you have to be? I see a drip issue, and , or a problem with
to much oil at the nozzle. Are these issues?

Thanks,
One of the better threads in awhile. Good stuff.

"Aaron Smith"

[altfuelfurnace]

The Metering pump is wired to my temp controler, so it turns on when the heater
block is up to temp.
I do have a three way solenoid valve in the loop between the pump and the nozzle
so it opens to the nozzle when the pump turns on, and opens to a small bucket
under my furnace to drain back most of the oil in the nozzle when it shuts down.
The bucket holds about a gallon and just dump this back into my tank about once
a week.

"Kevin Matheson"

[altfuelfurnace]

Aaron
I forgot to answer your other question.
As far as setting the speed of the metering pump, my speed controler on the DC
motor has a range from 0 to 10. My system needs about .75 GPH, bench testing I
found that 5 is about right. If I want a higher output I can uurn it up, but
also have to increase the air pressure a little. I look through the sight glass
to watch for a clean burn where the flame does not hit the back of my combustion
chamber.
Kevin

[altfuelfurnace]

I have a Buderous (KingBuilt) 150, its is really awesome, very, very
easy to clean!

steve kronimus

[altfuelfurnace]

I agree, in one year I have saved over $2200 and I will have a ROI in
less than 3 years with my Kingbuilt/Buderous boiler.

steve kronimus

[altfuelfurnace]

Hello, Kevin,

I am new to this, setting up a system now, but, from what I
understand, you have a pump feeding a siphon nozzle? Is that
correct? Is that in place of the constant level tank?

Thanks,

Matt

[altfuelfurnace]

Matt
That is correct, I do not have a constant level tank. I tried that first with a
float switch and after a couple to times that the switch failed and had oil all
over the floor I switched to the metering pump,and haven't looked back sence
Kevin

[altfuelfurnace]

Having spent sometime experimenting with babbingtons I have decided to buy one of Craigs kits to start making savings this winter, I am setting up a second boiler outside the house in a small new boiler shed.  I will probably be running wmo since all the wvo around here is committed to the biodiesel makers. Since I don't have a siphon tank and I do have oil pumps and small low speed electric motors it seems as though it might be best to move directly to a metering pump setup.  I would need to build a pwm speed controller but I think that's possible.  My other experience of PWM controllers is in controlling the wire feed rate in a mig welder, in some of these when the trigger is released and the wire stops the controller reverses for a moment of two to pull the wire back and make for an easier arc start next time.  The same approach would seem to be a possibility with the metering pump, reversing it at switch off and removing the pressure from the nozzle and killing the drip.  What do people think? does anyone have a circuit for a PWM with this feature?  it would seem an ideal application for an Aarduino driven controller.

John

[altfuelfurnace]

John
You will not regret getting one of Craigs kits, work very well and good
instructions for instalation.
I'm not sure what PWM stands for, but reversing the pump should work to prevent
nozzle drip, it would take some expermenting to get the timing down. You want
to get the oil just below the center line of nozzle so that when it expands from
heat it will not drip out the nozzle. For my simple mind it was just easer to
install a solonoid valve.
Kevin

[altfuelfurnace]

I'm following this to see how it goes. I originally tried a level tank outside in NH (cold). After much trial- no fuel or way too much, I swapped to a metering pump.
I wanted to add Craigs heater block, but he didn't recommend it below 50 degrees. You will have to overcome the issues of starting up when cold.

Maybe a kerosene startup and flush?
Maybe electric heaters for the air?

Heating the small amount of fuel won't make much difference if you are blowing 10 degree air into it

As for the level of the fuel in the nozzle, it shouldn't matter. The metering pump should add a controlled amount of fuel. The blower will add a controlled amount of air. At the right ratio, it will burn.



Carl

[altfuelfurnace]

PWM stands for Pulse Width Modulation; it is a method used in motor driving to
control speed by varying on/off pulse frequency and duration.

"Chris Brunner"

[altfuelfurnace]

Pulse Width Modulation.

It's sort of like turning on and off the switch very fast. You can
control the on/off periods to have it move slower.

diyernh