CONVERTING from wood to oil

[maple flats]

After 20+ yrs boiling using wood fired evaporators from a 2x3 to a 2x6 then a 3x8, I recently sold my wood fired evaporator. I bought a 2x6 wood fired raised flue evaporator I plan to convert to oil.
I have questions about how to proceed. I have a good friend who converted a larger evaporator to oil, since then he sold that rig, moved several miles away and bought land much closer to me. He now uses a oil fired 2x6. He "thinks the nozzle is 3.5 gph and the burner is a Carlin 301" My question what burner and nozzle is best for an oil fired 2x6 or good? Is the Carlin 301 best or is another best or can either do equally well? How about brand, are others as good and if so which are good. Is a 3.5 gph nozzle the right nozzle to use on a 2x6? Are there a few options that do very well?
For oil, do those who burn oil and have no heated storage for the oil use simple winter mix oil/kero blend?
For years I've had diesel delivered and I try to buy it before the oil is blended. I use Power Service additive and I've never had jelled fuel in my tractor nor my truck. (I have 2 diesel tanks currently, one is for off road and one is for on road) both get the Power Service. My thought is that jelling won't be a big issue for 2 reasons on the evaporator. When the sap is flowing the temperatures have moderated, and the fuel supply will likely have 2 lines, a supply and a return. As the fuel gets pumped to the burner and any excess is pushed back I'd think it would tend to raise the temperature some.
Where is a good place to get such a burner? I see some on Ebay, Facebook Marketplace and in Maple Trader classifieds as well as various vendors. Nozzles, I see choices, which is suggested, a 45 degree, an 80 degree or? Then hollow or solid?
I currently own a 150 gal tank that should be fine, I used it for 5 yrs for diesel at another location, but when I sold that location I brought the tank to my sugarhouse. I haven't checked to see if it has a low bung plug, but if not, I could get one installed, or can the oil be successfully drawn up thru a top fitting. This tank is an upright round tank. I have a good driveways from the road into the sugarhouse and I keep it plowed all winter so deliveries would not be an issue if I need a refill. I'm thinking a full tank might be enough for the 300 taps I might have in 2025 since I'll RO it to 8% or maybe even near 12%, my RO doesn't like going farther than 12%.
In the future I'm hoping to add up to 425 taps if I only tap my bush around my sugarhouse and I might possibly be able to rent about 50-60 taps from a neighbor who's dad planted some maples about 40-45 yrs ago, they are in 2 rows immediately adjacent to my eastern property line and running tubing would be quite simple.
My plan for the conversion is to pull the hinge pin, remove the door and replace the door with a 1/4" plate and mount the gun in that. I'd make it so, if ever needed I could remove the oil unit, put the original door on and burn wood.
My evaporator is a 2x6 with a 24x24" syrup pan and a 24x48" raised flue sap pan, (not like Leaders sizing where the label says for example 24x24" but when measured it's smaller. In fact I didn't measure my previous pans on my 3x8, I read the tags which said 36x24 Syrup pan and 36x72 sap pan. When set up there was also an almost 1" thick insulation seal between the two pans. I ordered a 36x36 syrup pan and a 36x60 sap pan (made by Thor in Quebec). When they arrived, I tried to set them up, they would not fit. I measured them and each was exactly as ordered. Since I had sold the original pans I don't know their length, but the new ones had a reinforced gasket between them of 1/4" thick, but the pan combination was slightly more than 2.1" too long. I ended up removing the base stack plate and made a new one so the pans fit fine.
I'm also thinking I may make a flip cap for the steam stack to keep things out when not being operated. Or I might get a China mans hat and screen it using SS screen.
Back to oil fired, I'm thinking the oil stack will need a barometric damper, correct?

[mainebackswoodssyrup]

Dave, we run a Carlin 301 burner with a 4 GPH nozzle on our 2x6 rig. Fortunately for us, we bought ours from a guy who owned an oil company so he did all the fine tuning when he had it. We get near 50 GPH with no preheater and an over-sized (not tight fitting) hood, which I think is pretty good. We have drop flue pans but the belly of the evaporator is not ramped like most. The flame stays high and hits the pans, maybe why he has a 4 GPH nozzle in it- to make up for the lack of ramp effect. I have played with the pressure some, a small adjustment can make a big difference. I attribute this to variation in fuel quality as it always seems to be if we fill the tank part way through the season, some adjustment is needed. Stack temp at 700 degrees is our sweet spot and I will adjust the pressure to keep it there. We have a damper and draft on the back but the draft stays fully closed and the damper is always shut, not doing much, if anything. If either one of those are open, stack temps shoot up.
In regards to fuel, we run 100% kerosene. That is what it was set up for. We tried a 50/50 mix of #2 and kero one year and it was terrible. The #2 is so much dirtier, stinks and leaves an oily film compared to straight kerosene. Then last year, the delivery driver screwed up and filled a tank with #2 instead of kerosene. I ran it for 15 minutes and shut it down. Luckily we have 2 tanks and that tank will be used for the heaters until it is gone. I have been wanting to try diesel as it is a little cheaper and should burn like kerosene. That is what our friend ran on his 4x15 CDL evaporator. But, after that bad experience trying #2 I have not dared to. Some day maybe I'll try it with a 5 gallon jug to see what it does and how it burns. So, I recommend kerosene or diesel. Stay away from #2 oil. If using diesel, adding Diesel 911 will eliminate the jelling concerns.

I think you'll find every evaporator is a little different and you will have to play with it some. Maybe even try a couple different nozzles. It's all about clean fuel and pressure for the most efficient boil.

[maple flats]

Thanks, that's a lot of good info. I have a raised flue and plan to insulate under the flue pan to help push the heat up thru the flues. The firing chamber will also be insulated. I'm thinking I'll put the ceramic blanket in, then half brick it. While half bricks will compress and lower the R value of the blanket insulation, if oil becomes hard or impossible to get (current world situation?) I could go back to wood in short order. As for power to run the sugarhouse I have solar on battery back up, but I'd need to get a different inverter for a larger portion of my solar which is grid tied only. If the grid goes down, that would instantly shut down.
I'll look for a Carlin 301.
I was planning to use diesel and maybe with kerosene mix, I'm not sure on that yet. I do use the Power Service diesel fuel additive for both diesel tanks now and slightly more than specified on the jug. For example if I order 200 gal I add a jug stating it's for 250 gal. I've never ordered less in the past, but if I use my 150 gal tank for the evaporator I'd likely order 140 or 145 gal and add the 250 size jug of power service on the first filling, then I might order 100-110 at a time and put in a jug labled as being for 125 gal. My issue with kerosene is that the btu rating is lower.
What concentration do you RO to? I'm trying to calculate how long a 140 gal load of fuel might last.

[mainebackswoodssyrup]

We don't have the new shack done yet so still boiling on raw sap at around 2%. Yes- we use a lot of kerosene. Getting it at the rack price helps. We'll burn 5:1 with raw sap. Last year was around 350G of oil for 72G syrup. We have a turbo 250 RO ready to go, probably not until 2026 season now. If we can get to 8% in one pass then we should be looking at a 75% reduction in oil. But at same time, 230 taps will go form gravity to high vac so we should process a lot more sap. Those are our numbers. Our sap is usually 2% to start the season and ends around 1.6%.
Any idea how much syrup you think you'll make? I suspect the 140G load will easily last a season, probably much more if boiling double digit sap.
Also- I wouldn't get too hung up on BTU's. #2 has more BTU's than kerosene but it burns like crap. It's dirty.........I think diesel is somewhere in between but I am not sure

[maple flats]

At my woods, all on 27" vacuum I used to get about 200-225 gal on 425 taps in a good year, in poorer seasons it was often as low as 100-130 gal or so. My sugar usually starts at 2.1-2.2 and goes down to 1.8. I usually quit at 1.7-1.8 even if the sap's still running but that was when I had 4.5 acres of blueberries to tend to. I sold the blueberries late last year. I now might continue to collect sap to maybe 1.5. I doubt I'd go any lower, at 1.5 I might need to do 3 passes on the RO to make the oil fired worth it. The farther I go with the RO the lower the pressure I need to run at and of course I'm raising the concentrate temperature with each pass. At 2% in or higher I run at 275-280 psi, second pass is usually 235-240. So far I've never run a third pass but I might guess with my RO I might need to run at 200-210 PSI, then I'd need to boil immediately or the syrup would all be very dark.
On the flip side I do well selling bourbon barrel aged maple syrup and that doesn't get graded by color. I've used my darkest syrup for that and it is my bast seller, it can even be black. I sell slightly more Dollars worth of that than all the regular syrups combined, but of course the markup is much higher. A 12.7 oz bottle sells for a little more than a full quart of syrup.

[BAP]

Diesel fuel is the same as #2 fuel oil with various additives for helping with injection pump lubrication and injection cleaning. In the winter time in cold areas, #1 or kerosene is mixed in up to a 50/50 ratio depending upon location to keep the gel point lowered. Depending upon the bulk fuel depots that the fuel supplier hauls out of, diesel and #2 fuel can be from the same tank, they just blend in the addition additive package for diesel as they are loading up.