About 1 month ago furnace would not start. I haven’t had this house long and the gauge looked pretty low so I assumed I screwed up and was out of fuel oil.
The oil company couldn’t get to me right away so I went to the gas station for 10 gals of diesel which I dumped into my oil tank.
Furnace would still not start.
Oil company filled tank with fuel oil.
Called Burner guy who replaced a plugged nozzle in Riello (Mectron) burner.
Its been a month with no problems except for (darker than the neighbors) black smoke coming from chimney when furnace is in operation.
Is the black smoke a result of the diesel fuel in my tank burning off or did the burner guy do something?
thanks in advance
Be Constructive
Gord
St.Margaret’s Bay NS
Edited 1/3/2005 7:29 am ET by gordzco
Replies
Something is very wrong and dangerous - you have a condition called backdrafting and the combustion gases are coming back into the house.
Those combustion gases can include dangerous amounts of carbon monoxide.
The problem could be a blocked flue, but there are other possible problems which can cause back-drafting
I strongly recommend not using the furnace until it and the flue are checked out by a good heating contractor. Like today -- ASAP!
And get and use a good carbon monoxide detector: one with ####digital readout on its face.
I don't know if the use of diesel has caused other problems, but the smoke coming back into the house must be dealt with NOW!
Sojourners: Christians for Justice and Peace
Thanks for your concern Bob. I don't have any smoke or smell coming into my house, I just noticed the unusual blackness of the smoke (little, not like a semi heading up a hill) on the weekend while I was up on the roof changing Christmas lights. I really hadn't noticed how black it was from the ground.
As I mentioned to Goldhiller, I'll schedule an appointment with the best I know tomorrow.
Thanks again,
Be Constructive
Gord
St.Margaret's Bay NS
Black smoke implies the furnace is running too rich, and wasting heating oil. Look over at wwww.heatinghelp.com for some ideas. The repairman should also fix the problem pronto.
Renaissance Restorations
Antique & Victorian Home Restoration Services
http://www.renaissancerestorations.com
Thanks for the link
I copied and pasted with no luck till I realized there were 4 w's.
There is alot to learn about oil burners
but I will be satisfied by knowning just a little
More
Be Constructive
Gord
St.Margaret's Bay NS
As previously stated..........the unit is running too rich. That black smoke is unspent fuel.
If your furnace guy replaced the previous nozzle with a nozzle of greater gallonage (that's a per hour rating to be seen on the nozzle itself or the package it came in) and did not adjust the combustion air accordingly, he left your furnace running too rich.
Or if he adjusted the combustion air and "blew it", same reason it's black smoke. Too rich/not enough combustion air allowed to get to the fire pot.
Or.....if he replaced the nozzle with one that has the wrong spray pattern, you can easily have the same result although the air setting was left untouched.
Or if he dinged the end of the correct nozzle when he installed it, it would effect its pattern and voila.......same potential result from fuel that is squirting or dribbling, instead of being atomized or is being tossed outside the prime combustion area.
Or if the old nozzle was plugged from crap getting thru your filter, the new one may now be partially plugged.............which can cause the same result.
Or if a dust bunny got in front of the combustion air intakes down by the pump during the shuffling of feet, etc........ same result. Chokes off the combustion air supply. That would be your potentially easiest fix. Remove any obstructions you see around those little air intakes. I've seen this happen more than once.
Low pump pressure can also result in rich burn as the fuel won't be properly atomized.
There's numerous other possibilities that can cause a rich burn, but it's likely one of the above.
And yes, this is a potentially dangerous situation as the soot produced can rapidly clog your heat exchanger and/or flue.
You need to get someone out there who knows how to set up an oil furnace and has the proper equipment to check the results..including the draft control. Once it is established that the proper working nozzle is in place for your unit, it has an unobstructed supply of fuel, the pump pressure is correct, and the HE and flue are unobstructed........then the rest of the adjustments can be made. The tests should give results for cleanliness of burn, final flue temps resulting from the burn, barometric over-fire draft adjustment and finally heat rise at your registers to insure your blower is efficiently capturing the generated heat.
All of the combustion and the draft tests and adjustments should be done after the unit has been running non-stop for 20 minutes.
You haven't hurt a thing by introducing some fuel from the diesel pump. That's what your unit burns. Diesel fuel.
Edit: Let me add this......Even if the fella put in the correct nozzle and you find some bunnies blocking air ports and the removing of them rids you of black smoke.......I'd still get someone out there with the proper test equipment and who knows how to use it. Assuming that the unit was properly adjusted when you took possession of it, isn't necessarily a wise thing to do. You could be sending more BTUs up the chimney than necessary even if the burn appears clean to the eye.
And one more edit: Where does the make-up air come from for this burner? Is there a sufficient fresh air supply to the space where this unit resides? If not, then the furnace cannot acquire adequate air to supply its combustion and draft needs......no matter how well it's adjusted. Rich burn could easily result from just that.
Let's say that it resides in a utility room and the door is open while the furnace guy does his thing. When done, the door is closed and he leaves. I'm sure you catch my drift.
Much freezing rain here today that prevents road travel, so while I'm sitting here chewing on your siuation....one more semi-possible cause comes to mind. Mounted on the burner assembly of these oil-buring units is a device known as a fire-retention ring. The burner assembly must be removed in order to place a new nozzle and these FR rings have been known to come loose and work their way down toward the nozzle and can then effectively obstruct the fuel pattern. The only way to determine if this is the cause is to remove the burner assembly and check it out. IOW, take nothing for granted.
Knowledge is power, but only if applied in a timely fashion.
Edited 1/3/2005 12:00 pm ET by GOLDHILLER
Edited 1/3/2005 12:20 pm ET by GOLDHILLER
Edited 1/3/2005 12:41 pm ET by GOLDHILLER
Thank you so much for all of the information, I will definately get the furnace checked out pronto. The guy who fixed me up may not have been the best in his business and was recommended to me by the fuel oil company. There is another company I trust but they were too busy to get to me. Now that I have heat, I can wait for them. Fuel oil ain't cheap and like you say, I should be making the best of it.
Thanks again.
Be Constructive
Gord
St.Margaret's Bay NS
Since we're expecting 8-12" of snow, starting at 7 tonight along with 35 mph wind………..which will fall on top of that ½" sheet of ice out there….. I guess I'll take a little time here once to spiel a bit more on OF heating units…as some of this may prove of value to you. Might be food for thought anyway.Most folks who get/have an oil-fired unit of/rated for X number of BTUs, think they have to live with that and so they do. But this isn't the case at all, in most instances. Unfortunately when it comes to OF units, nothing is usually done to eliminate the waste of what could well be, an initially "over-sized" firing. If we lived in a constant unvarying ambient climate, truly efficient heating would be a much easier ideal to meet. But we don't and so the best we can usually shoot for is a unit that runs 100% of the time during the periods of the most extreme requirements we encounter throughout the heating season……… and when required to do so, then barely meets our needs. Usually the installer does not consider downsizing the nozzle on a new unit as that would require extra time on a fixed bid and if you want it done later, he makes more coin doing it for you. The HO usually doesn't know this can be done or decides they don't want to pay to have it done…..so it doesn't get done. For instance, the OF forced air unit here came with a 1.5 gallon nozzle installed. That's the way it's shipped; with the largest nozzle the firebox and HE can handle. Very wasteful for this house, as much starting and stopping results…and more BTUS lost up the chimney. But eliminating the potential waste with an OF unit isn't that hard to do. Experimentation begins by changing out to reasonably smaller nozzle…….. (while still falling within the range of nozzle sizes that your unit can handle-see manufacturer's specs) …….to see what size is really required to barely meet your abode's extreme needs. This change of sizes then requires resetting all the combustion and draft settings, etc…(but that part isn't of a great financial consequence to me as I do the work myself.) I initially dropped to a 1 gallon nozzle here and ran that way for a winter, paying attention to what proportion of the time the unit was actually firing when it was -25F and 40 mph against the house. Still ran less than I thought I could get away with, so I changed out to a .75 gallon per hour nozzle and readjusted the combustion and draft. Bingo……..pretty much. The most severe winter nights (-35 thus far) have found the unit running about 95% of the time. This is the smallest recommended nozzle for this unit, so I'll live with that remaining 5% and call it "emergency buffer". (Nozzles generally come in increments of about 1/10th of a gallon an hour, so finding one that just cuts the grade, isn't that hard to do.) Point being, if you have an OF unit and it does a lot of short-cycling in extreme conditions…….you can likely downsize that nozzle a ways and get much better overall efficiency. But once the "right" size nozzle is found and the unit tuned to it, don't change it unless you're also prepared to redo the tune-up for combustion, etc. And don't let a furnace guy toss one in there that's larger or smaller or of a different pattern just because it's the one he has with him at the moment. Many problems can and will result unless adjustments follow; that for a nozzle that throws the right pattern for your unit. Tossing in a nozzle with the wrong pattern has no real rectification, except to put in the right one. Same holds true for electrodes. Replace with only the electrodes specifically made and recommended for your unit. While a guy can usually jury-rig a different set to get a unit up and running in an emergency situation, they won't likely have but 20% or less of the life expectancy of the designated set from the manufacturer of your unit. I also highly recommend that OF owners keep a new nozzle and set of electrodes on hand at all times for their particular unit and set-up. These critters don't have much of a history of breaking down during the summer. They only seem to quit on you when you need them. <G> And your service folks may or may not have the nozzle and/or electrodes you specifically require in stock, let alone on the truck. The other stuff like transformers, fuel filters and CAD cell units are much more universal, so the odds they'll have those with are much better. Anyway, if you've ever paid attention to what proportion of the time your unit is firing in the most extreme of circumstances, it may give you some guide as to whether you might want to consider a smaller nozzle since the folks are coming to service the unit anyway…..and as to what proportion of downsize would likely still get the job done for you. And don't forget (or let them forget) the anticipator setting on your thermostat. That can also cut into your efficiency........as can too slow of a blower speed to capture that heat. Note that there is a relationship between the flue's TT and your blower speed. Capture all you can and still meet the manufacturer's recommendations for flue temp. Gotta clean air filter in there? Knowledge is power, but only if applied in a timely fashion.Edited 1/4/2005 8:42 pm ET by GOLDHILLEREdited 1/4/2005 8:54 pm ET by GOLDHILLEREdited 1/4/2005 8:56 pm ET by GOLDHILLER
Edited 1/4/2005 9:18 pm ET by GOLDHILLER
trade ta an ice storm fer yur snow...
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming
WOW!!! What a Ride!
Fat chance.
;-)PS- Reload yer window. I had to edit my rambling.
Knowledge is power, but only if applied in a timely fashion.
Edited 1/4/2005 8:48 pm ET by GOLDHILLER
>>All of the combustion and the draft tests and adjustments should be done after the unit has been running non-stop for 20 minutes.Why after 20 minutes?I don't see many oil setups in my area, but it seems to me you get a lot of info during and just after lightoff
Sojourners: Christians for Justice and Peace
Info at start-up and shut-down, yes. But the info at start-up will only tell you how the unit performs when it is not yet running at terminal temperature.For instance, if you test the cleanliness of combustion before the unit has reached terminal operating temp, it will show somewhat dirty combustion as opposed to what is actually happening once it has reached TT.The warmer the components in there, the better the vaporization and combustion of the fuel. Same thing when your car engine warms up to operating temps. A final carb tune isn't done on a cold engine for the same reason.Trying to adjust the combustion air in an oil-fired burner, which has not reached TT, will lead you to throw more combustion air to it to clean up the burn and get an acceptable CO2 reading and smoke test results. Left that way, when the unit finally reaches TT, your fire would be too lean and that results in higher operating temps which is hard on the fire-pot and the HE.And only after your flue and chimney have reached TT, can you get an accurate read and adjustment on over-fire draft. A cold chimney doesn't draft as well as a warm chimney. An exterior masonry chimney would usually skew this reading even more than an internal chimney and so we want to make sure the flue/chimney has reached its TT.And only after the unit has reached TT can we get an accurate read of the exhaust flue temp, which is taken just prior to the barometric draft control.Unfortunately, alot of guys who tend to oil-fired units don't always heed these principles and inefficient operation results and/or the life expectancy of the unit suffers. Around these parts there are far fewer OF units than 20 years ago and the number of guys who know how to adjust one, or even care to tend to them at all, has greatly diminished. They don't want to get that fuel-oil smell on their hands. <G> Knowledge is power, but only if applied in a timely fashion.
Edited 1/4/2005 1:17 pm ET by GOLDHILLER
I certainly agree with your well worded summation, especially the TT statement.
Too many of to-days 'so-called' Techs do not spend enough time on the job to do a proper efficient tune-up
I'm not saying all the Techs are slip shod in their methods ,but having done this type of work over the years I know what is involved.
i am now 7 years retired from the Trades I was certified in , and have been fortunate to have a real qualified oil burner Tech with ALL the testing equipment to do a thorough job on my own unit.He also is a believer of running it 15-20 minutes to really get a true picture of whats going on, and set it up accordingly.
It pays off in the long run. Hube
Thanks for the info.FWIW, I've found that gas fired appliances usually stabilize for draft after 2-3 minutes.And with an oil burner, shouldn't your draft be regulated by the barometric damper and thus not get any variation, at least after the initial minute or so?
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Sojourners: Christians for Justice and Peace
"And with an oil burner, shouldn't your draft be regulated by the barometric damper and thus not get any variation, at least after the initial minute or so?"More or less....yes. But how shall we initially set the barometric draft damper and to what.....unless that setting is done after the unit and the chimney have reached TT?I'll tend a unit that needs immediate attention on any day, regardless of outside weather conditions.......but.......ideally this barometric draft adjustment should and can only be accurately set on a day when there is little, if any wind at all. If it's gusting outside, varying the pull on the flue, arriving at a good initial adjustment is virtually impossible. The draft would/will vary from minute to minute or second to second. And so I return on a more favorable day. Knowledge is power, but only if applied in a timely fashion.
There are many ,many differences in the set-up between a gas burner and an oil burner . There is no actual comparisons at all associated with the two complete functions.
"atomization" as in an oil firing gun is a completly different set-up compared to a free emission type fuel, such as nat. gas