Oil-fired boiler, huge amounts of soot

[spamTHISbrp]

Oil-fired boiler, every once-in-awhile it spits out huge amounts of soot, 1st time thought it was a home-grown outside combustion air pipe that had slipped 1/2 off and blocked the intakes, because when I took that off, it ran fine.

A month after that (monday), it did it again, called the service guys. They said the electrodes were too far apart, was causing late ignition, and that it wouldn't burn properly bacause of that.

Today, same thing. Wouldn't even start, it was running so 'rich'. Noticed the air intake was all the way shut, leaving just the small 'default' openings on the pump face open. I talked to the service guy, priced out a weekend service call. Ummm, no way, given that they supposedly 'fixed it' on monday.

I asked how hazardous it would be to try opening the air inlet- he said it might get me through the weekend, since the prob might be a bad nozzle that wasn't atomizing sufficiently.

Opening the air intake a bit fixed the hard ignition/smoke, but if I opened the air intake up beyond a small amount, it would blow exhaust out the damper door, and this is a unit with a power vent.

So air intake closed (as the service guy left it), blows smoke/soot and stops running, open a little it doesn't smoke and the damper draws air from the room (garage), opened too much and it blows exhaust out of the damper door and into the room.

Yes, I know, whatever tuning this thing needs is shot to hell, but its running without soot and the power-vent is drawing plenty of air out of the room via the damper, so I'm going to run it until monday.

What the heck does it sound like the problem is? I'd really like to have a list of possible issues to discuss with the service guy, as I really want to get this fixed once and for all.

What I see is that the air intake was completely closed, and the other air intake openings are very small, so that just seems a little odd. maybe with a clean nozzle that's OK? Maybe someone put a very small nozzle in this thing, and the air intake really can't be properly adjusted for that small a nozzle?

Any thoughts out there?

Dave

[Dr. Hardcrab]

The electrodes being too far apart have nothing to do with the way it burns. Yes, you can get late ignition, but if it's sooted up, there IS something wrong with the air mixture. Sounds like you need to find a different company that fix it properly if these guys don't.....

[Mark]

can you look into the view port? (make SURE you close it tightly when done looking)

too much air, fire is small and white and lots of heat goes up the flue

too little air and the fire is fluffy and red and smokey and lots of soot

better to err on the side of a little too much air rather than too little...

too little air also creates CO

get a probe thermometer that you can leave stuck into the flue pipe and you can monitor the situation...

if it chages day to day you need to figure out if the oil or the air is changing... you need the right combination of both...but you knew that..

yeh I think the electrodes are pretty much not involved once it ignites, so if it ignites ok probobably not an electrode problem...

Mark

[mm]

I couldn't follow your post. Did you get a new nozzle? Did they come out twice? Which time did they put the new nozzle in?

You leave sentences out of your story. Twice, iirc, you say you called them and you were told things, but you don't say whether they came out or what they did if they did come out. Very hard to follow..

For example, you didn't even say if they readjusted your electrodes or if they replaced your nozzle.

Adjusting electrodes is so little work for what they charge for a service call, I would think they would have replaced the nozzle too and adjusted the air, although in practice only one guy has ever adjusted my air. They just look at the flame and figure the adjustment is ok. (That's why I'm not very happy.)

I don't have a boiler but I have oil forced air. The plate near the burner says what sort of nozzle is to be used. The little plastic container tube says what kind of nozzle was in it (and no one I've dealt with has taken the tube with him. They just leave it here) and the nozzle itsself has its spray pattern code embossed dimly on the side.

Remove NOPSAM to email me. Please let me know if you have posted also.

[Bubba]

Dump your tech and find a company that knows how to use and interpret digital combustion efficiency equipment. You cannot guess at a flame by looking at it. It can soot up terribly and/or waste hundreds of gallons of fuel oil. Get it done right by someone who knows or get that thing out of there and install a gas furnace, propane, electric, heat pump, or geothermal. Bubba

[HeatMan]

You can no longer set the fire in an oil burner by seeing it.

Small and white and fluffy and red doesn't mean squat....

[spamTHISbrp]

They have come out once, adjusted the electodes, and I'm going to speak with the service manager before they come out again. I want to hear how they're going to adjust the mixture, how they're going to check the nozzle to see if it needs a new one, and I'm going to ask they return the flue thermometer that was on the boiler before the service guy showed up last week.

nozzles, a small one for longer cycles, a large one for shorter cycles, I'm guessing the ideal is a nozzle size such that it just maintains water temp for a max load (heat and hot-water) situation.

dave

[Doug]

Yep, I've heard the above from you and some other pros.

However, I've adjusted Beckett AFG burners and Carlin burners dozens of times by eye. I'm a landlord and generally my purpose was to get heat back on ASAP so the tenant wouldn't have the housing code folks all over my tail. In most cases, I later called in a pro to set them up via instrumentation.

In each case, my "eyeball" settings were within 2% of peak efficiency, based upon the pros' CO2, stack temp and soot measurements.

Why don't you try it yourself? After repeatedly setting up most modern flame retention burners by eye, I suspect that you'll get pretty close to the ideal.

Half the time, if I call in a "pro" to do it, they give me dirty looks when I demand they use instrumentation...

Doug

[Dr. Hardcrab]

2% can mean a big difference in some cases.

You really need to use the proper instruments, but I'll admit: On older stuff there is nothing wrong with using the old eyeball method. and if you have been doing it long enough, you KNOW what looks right and what doesn't....

[spamTHISbrp]

Ends up the service guy left the air setting right where I left it.

-D

[Dr. Hardcrab]

Since you don't give a name, we shall now call you "FlameEye".......

;-]

[spamTHISbrp]

Actually, I did it by watching the draft, as I was just trying to get a 'safe' working solution.

With the powervent, too much combustion air and it would come out the damper door (bad, bad, bad!), too little and it would soot up. I basically split the difference between the 'soot' setting and the 'blow out the damper' setting, erring a little towards the sooty side.

Dave

[Dr. Hardcrab]

Power vent??!!

Gawd I hate those. Necessary evil, I guess...

[flansp78]

When was the last time the boiler was brushed down? If they are going to do a complete tune up they should also brush the boiler heat exchangers. Also, check your chimney. Make sure you have no blockages or partial blocks. Remember, in order to make a fire you need, spark, air, and fuel.

[spamTHISbrp]

Issa noisy bastard, but having the fumes sucked out is a minor plus.

Dave