A Roger Sanders' garage heater in Oz

[p38arover]

I mistakenly started this project thinking it would be relatively easy and successful and that it would be more economical than buying an LPG (propane) heater for the garage. 

I was wrong on all counts.  Thankfully I haven't yet cut a hole in the roof of my garage for the flue!

But to start at the beginning....

I'd read about Roger's design and decided to try it. 

After a few years of procrastination and procuring parts, I made a start. I had been using the secondhand 6" flue I'd bought with a wood heater I'd also bought off eBay  - but a recent acquisition of an old small water heater from a friend got me motivated.

I bought an aluminium dish and needle valve off Roger Sanders but now I see some of you have melted yours.   I don't want to melt it as those two items cost more than everything else (cost A$136 by the time I had them).

I had been slowed up by trying to work out how to put a 6" flue onto the heater. I made up a cardboard template and a friend's son, who is a boilermaker with his own business, made the adapter up in steel. I welded it on, cut a circular hole in it (with a cutting disc in an angle grinder) and added a 6" ring to drop the flue over.  For scale, the air intake is 100mm (4 inches) in diameter.







I've been testing it with wood I have for the other heater which has now been removed.



That hole in the door has a plate over it when oil burning.



Next job was to do the oil feed. I bought a glass bowl gauze screen oil filter and mounted it above the heater.  The oil tank is a plastic drum up in the rafters of my garage.  I've piped it down to the oil filter then via the needle valve  to a pipe into the air intake.











The flue is temporarily routed through the fibro-cement garage wall and up the front of the garage for testing.





I now have a drip tray underneath to catch any small spills of oil - yes there have been some.  The heater is lifted off the floor about 50mm, sitting on some square tubing.



Now to the problems.  It simply doesn't burn hot with the Sanders burner so it smokes excessively.  It is also very easy to extinguish the flame so it has to be watched constantly.  The burner is left with a thick filthy black gooey mess.  Nothing like that shown in Roger's booklet.  The temperature on the side of the casing only reaches 120-140 deg C but with wood, the temps are well over 300 deg C (my Fluke optical temp reader maxes out at 299 deg C)

Today I tried something else.  I took out the aluminium burner but left in the steel disc on which it sits.  I then started a wood fire under the disc to get it hot and, after it was hot, started the oil flow.  It burned somewhat hotter and I was able to occasionally get the flame flower Roger mentions.

Usual burn which is very smokey:



And when I get the flame flower, the smoke is barely visible:



Now my questions are:

• How do I get this thing to burn hot so that it doesn't smoke?
• How important is it that the front door be air tight?
• Is the distance from the air intake to the burner critical?
• Is my flue long enough.  Would lengthening it help?  I've avoided making it to high to minimise neighbour interest in the smoke and smell - I don't want the council around.

I'm sure I'll think of more questions.

So far, I'm up to $485 for this build and it's beyond the point of no return.

As an aside, has anyone had problems with their council? It's ok for you blokes in the country but I'm in a city suburb. I checked my council's website and they only mention requiring approval for wood burners. Very likely an oversight but I am not gunna tell them!

The temperatures that some claim can reached by the oil heater look a bit scary for where I currently have the heater for testing. The longer term would see it moved further away from the timber wall frames.  I've put fibro-cement sheet between the flue (which doesn't get very warm - only about 100 deg C) and the timber frame.

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[Russ]

Hello Ron,

Unfortunately I have no experience with this type of heater, but I did want to comment on your workmanship.  You have a very nice build there and I hope you can get it burning correctly.  If you can, you will have one nice setup.

Good luck, I hope it works out!

Russ

[p38arover]

Thanks Russ.  I'd love to get it working properly.  I very nearly installed air conditioning in the garage to cover summer and winter.  Winter isn't that cold here but summer is flamin' hot - up to 45 deg C and that's outside.  The garage is far worse so in high summer, I don't go out there!

However, to do that, I'd have had to run new underground power cabling to the garage to get the current carrying capacity I needed.

[Wrench]

I know this is an old thread, but your picture of that glass drip valve caught my eye.

I could NOT get my system to burn hot AT ALL with that valve in place! I found it was restricting the flow too much. I had purchased mine off eBay, but it looks identical in every way to the one in your picture above. I tried drilling the passages larger ... but that ended up defeating the shutoff valve, rendering it pretty much useless to me.

The second I removed that valve from the equation, the system ran right up to 900°F PLUS!

Hope this helps.

[p38arover]

Thanks for the reply, Wrench.

I've removed the chimney at the moment but can reinstate it to try again.  I'm not sure why removing the needle valve would help as I can get so much flow with it in place that the conical bowl overflows.

How do you control the oil flow now?

Ron

[Wrench]

Ahh ok, that sounds like your valve is working the way it's supposed to work. Sounds like your problem is unrelated to oil supply. Mine is also a totally different design from yours as well. You can check mine out here - it's about as simple and low-budget as you can get: http://wasteoilheaterforum.com/index.php?topic=291.0

Just looking inside my valve when I got it, I could see just a 1/8" opening - I suspected mine would be a problem before I even installed it.

Right now I have a brass needle valve that I just count the number of turns out from fully seated. Sometimes I forget where it's at and flood things, but I'm still learning it. I've pretty much got the hang of it now. I had burned some fryer grease in it once - that was a steep learning curve! Much harder to get lit, and it flowed MUCH faster. The setting I used for WMO had the WVO pouring out the front ... 

Anyway ... from my work with engines, I know to make a fire you need the right amount of fuel, and the right amount of air (ignition and compression don't apply here). If things aren't right, it's either one of the 2 in this case. Another variable is the mass of the burn pot/plate/chamber .. or what have you. More mass will take longer to warm, but will hold heat longer resulting in a more complete burn. I've seen folks on Youtube add thick plate steel with holes drilled in it above the fire - this supposedly results in a more complete burn. One guy added a brake drum on top of the plate steel - his burned pretty clean ... but I don't know how hot things were, or how much oil he was feeding to make a judgement as to if that works or not ... 

My unit will smoke pretty heavily when I get  between 750° - 900°F +  glass temps - I usually need to crank it that high just to warm up the large, uninsulated space I work in.  The hotter within that range, the more smoke I get. It will blacken the glass, and make a haze in the shop. Once things get up to temp, I'll turn it down - anywhere between 500° - 650° on the front glass will have zero smoke. If I wipe the soot off the glass, it will remain clean. The fire will blind you, too - really bright white. 

When starting the fire, it takes quite some time before I'm able to give it 100% air. It will blow the fire out. If I restrict it, it will run, but not hot at all - maybe 200° -300° on the glass - and that's only after it's warmed up. If cold, any forced air at all will blow the fire out, or make it pathetically small ... which means no heat. 

I'm sure with a little tinkering you can find your issue. Keep at it. 

[p38arover]

Sorry about the delay in replying Wrench.  I had the heater pulled out over summer (when you replied) but, as it's now winter and the coldest in 30 years - it's down to close on 0 deg C (32 Deg F) at night and only 16 deg C during the day - I'd like to get it stoked up again.  So I'm back at it and my wife says I'm smelling like an oily rag. 

I'm probably wasting my time with this design but I hate to throw away all the money I've spent.  I'm considering getting an LPG heater for the garage.

Unfortunately, I need to do the testing at night to avoid letting the neighbours identify the source of the smoke. 

[jbartlett323]

Wow, can't believe I missed this setup!  Very similar to mine, but I have custom made a manifold/burner, as both the MEN design and the Sanders design leave A LOT to be desired.  See mine here: http://wasteoilheaterforum.com/index.php?topic=409.msg2026;topicseen#msg2026
I think you have a few more bux tied up in yours though, all said and done I think I'm about $120US into this project, mostly in flue pipe.

To answer a couple of questions from your OP:

It is very important for the entire body to be air tight, including the door.  I had rust holes in the side of my body (hence why it was discontinued as a water heater), once these were plugged, it ensured all air was coming from the intake and therefore mixing with my fuel correctly and not causing a potential build-up of un-burnt gases in the body (which could theoretically explode.  Theoretically... well, actually kinda in practice, but that's another story...).  I am still working on getting the door sealed to my specs, the natural bow is kind of a pain...

The distance from the air intake to the burner is crucial!!  I assume you are using a cone of some sort?  If you pipe is too high/cone is too big, your air will spread in the body too much, basically negating the needed air volume as it passes around the outside of your burner and out your flue.  Too close will obviously have the opposite effect and not burn efficiently, as you are only burning in the middle of your burner and pushing un-burnt gas out the flue.  You will have to adjust this to meet your burners requirements, and I have had to fiddle with mine quite a bit before finding a happy place.

The longer the flue the better in draft systems like ours.  More flue means more heat in the flue.  More heat means more convection.  More convection means more air volume. More air volume means higher fuel potential, but also means you burn more fuel!  So again, you have to find the happy place.  IMO, your length is fine.

Finally, To burn hotter, ditch that burner plate! 
These heaters typically work on 1 or 2 different methods.  The Sanders burner that you are using is simply burning a pool of oil (standard method 1).  Obviously, it is never efficient to burn a pool of anything, you want to burn it as a gas not a liquid.  Once you reach Full Operating Temperature, all your oil will be gas, but reaching FOT with an in-efficient system is very hard. 
Method 2 usually includes some sort of "combustion chamber".  As was mentioned above, the Mother Earth News (MEN) style of burner uses this concept.  You use 2 plates with holes drilled (I used a small skillet and 6" dia. plate), spaced about 1.5" apart and closed on the sides.  Oil drips on top plate, is gassed and past to the "combustion chamber".  in this area is where you want your main fire to happen.  This was the first style I had tried, as it made more sense to be more efficient.  But I quickly learned it is not.  Still very hard to reach FOT, sooted like mad the whole time, and after about an hour of running the top plate holes would become clogged and basically became a Sanders burner.  Cleanup was a PITA, and it was required every time I wanted to use the stove. 
I designed my new manifold using both principles and added the idea that the more surface area the oil hits, the more likely it is to get hot enough to gas.  I now rarely clean it, have little to no soot (except on start-up of course), and have no problem getting the guy to put out as much heat as you could want.

I'm kinda in the same boat as you with my city.  What they don't know wont hurt em.  I try my best to keep smoke/soot down, again why I built a new manifold.

And yeah, if you do any of the above, move that baby away from the wall or put some sort metal/fire protection between it and the wall.  I have my wall of my 100% wood construction shop lined with sheetmetal that I stood off from the wall with rubber feet.  Wall stays nice and cool, the sheetmetal gets hot enough not to touch!  Once its running like it should, that body will be Red Hot.  I've had mine light up my shop well enough to see with the lights off type red hot.

Hope some of this info helps!  Keep tweaking that guy and it will keep you nice and toasty!