Stack Temp Too darn high?

Liberal Lenny

Hello People Happy Holiday wallies, please help me.I have a Slant Fin sries xl-2000/xl-3o with an Beckett AFG/F3 burner, running a nozzle Deavan 1.00 gph/80 degree w, 100 psi oil pressure, new filter, oil line blown out, pump screen new, nozzle new,burner and boiler cleaned.When I'm adjusting the air shutter ( starting at 8, Slant Fin recommended), the shutter is set at 0. My stack temp is over 700 degrees, my efficiency is around 73 %, if I lower the air shutter to 6 the burners seems to run rough but the efficiency goes up, how far can i push this guy?I looked at the flame but my eyes are not great, so I have a Fyrite Pro Combustion Gas Analyzer ( just bought it, really cool)I'm afraid that this will just soot up and I'll back to cleaning again.What should I expect for efficiency, any of you guys experts on Slant Fin Boilers with Beckett burners, should I change the burner to a Riello or a Carlin, what am I missing ?
Any help or suggestions.
Thanks guys this is a great forum.

Jim Davis_3

Your numbers would be more helpful if you would give your Oxygen reading(O2). Would be able to get better combustion if you used 140psi pump pressure and a .85 80 degree solid nozzle. This would allow you to operate with less smoke at a lower O2 reading which would reduce your stack temperature. Also, what is your over-fire draft at the burner?

Unknown

Call Slant/Fin

The number is 800 873 4346 in Tech Service.

Noel

Liberal Lenny

Stack Temp

Jim
I remove everything clean evrything, except the chimney which should be cleaned but drafting well, so I ran some more numbers CO 2=9.8
O2=3.4
CO=92 ppm
Excess Air= 17.9
Stack Temp= 518
Breech Draft= -.02
Efficiecy= 78.7 %

LIBOB

End Cone

I would go with an F6 end cone with that 1.0 nozzle @ 100psi. I never use more than a .75 nozzle with an F3.

Weezbo

hello ....

i really like Slant fin...and i really like riello....i really like tiger loops combos....however, my thinking is make the best of what you have at the momment ...that way things have a way of getting better.i not all so keen on beckey burners however i have fixed nearly every and any oile fired pos imaginable your stack would be better off down a few hundred degrees easily....and as you have set the draw band and the thing is smokin i have to think in my mind you check that pump pressure again first...and just for the heck of it set the draw band on 4.5 and fire it one time for me first...does it start? and run? what is the smoke # is it a two ? shut it off does it "Flutter"?

Jim Davis_3

If these are your numbers 518 degrees flue temperature then you are fine. Your analyzer is set for natural gas so the CO2 calculation is wrong, You would be at almost 13% CO2 with an O2 of 3.4% CO2 is just a calculation not a real measurement. Your CO is slightly on the high side which would still make me question the nozzle and pump pressure. It may run fine all winter but will end up with quite a bit of soot in it. Check your CO spike when the burner lights, 1st 45-60 seconds and when it shuts down last 45-60 seconds. If they are above 100ppm you may soot up before the winter is over.

Liberal Lenny

Slant Fin Rocks!

Thanks for all your help,I will be testing tommorow after the chimney is swept.I am interested about why we would change the nozzle and boost the pump pressure, what about the manufactors specs, this is something I'll have to read and learn more about.Sounds really cool, like when I used to build hot rods, always looking for more horse power.
Thanks Again, you guys are the best.God Bless

Weezbo

atomization *~/:)

soot_seeker_2

something's wrong


something sounds wrong with those numbers. the co2 & o2 should add up to 16.9% or 17% on your fyrite. it sounds like #2 fuel oil wasn't selected? the excess air sounds low & the co sounds too high. you should be able to push that c02 up a percent or so - but i wouldn't be doing anything without a smoke tester. i don't see how you can push the co2 up to optimum without checking the smoke as you go up. you'll probably get better numbers across the board if you kick the pressure up to 120-125psi (assuming 1.12gph is ok for the boiler - or downfire to .85) but like these guys said, get the spec from the slant-fin first before you adjust - sometimes they specify not only the nozzle size & pattern, but also the make (delavan, hago, etc) of the nozzle as well.

safety first. good luck.

ss

Rookie

Weez ? *~/:)

Does not compute *~/:) = ?
%-(

Liberal Lenny

Fyrite Tester

I will double check my settings and give you guys some better numbers.Thanks for you help.