I have a oil furnace in my friend’s home. This furnace is a Lenox Elite with a Beckett burner. It is connected to the central air unit and looks like it is venting out of the chimney stack. When I opened it to take a better look, I saw a powdered substance inside? Is this soot? If im correct this furnace is a high efficiency condensing unit. Can someone help with some info? Trying to do my final report and of course the newbie is a scratching his head again. Any feedback would help. Thanks in advance.
Post the ‘Data Plate’ photo.
Typically a condensing furnace will use PVC pipe for venting, traditional models use metal flue pipe.
Soot is a common occurrence with oil boilers or furnaces when the burner isn’t operating correctly or there’s incomplete combustion.
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What does that EnergyGuide sticker reads on the furnace, it’s too blurry for me to read?
Yes this furnace uses PVC pipes for venting however do you know what this is? Refer to the photo below.
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Barometric draft regulator.
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I might be recalling dated info but I’m not aware of any oil furnace that is 90% or better efficiency with respect to fuel usage. I remember talking to an HVAC guru at a conference probably 20 years ago and he said (at that time anyway) that condensing oil furnaces just weren’t feasible due to the impurities in the fuel and in the combustion process. It made for very dirty condensate that would clog pumps or drain lines and lead to other problems. Things well may have changed since then. I rarely saw oil furnaces in Oregon and here in Maui even less (actually never).
As for OP’s questions… that barometric damper sure looks like it’s attached to a metal flue that would be associated with an 80%(ish) oil furnace. Soot? Yes, definitely possible and common with oil furnaces. Oil (compared to natural gas or propane) is a very dirty fuel and service is much more critical. Nozzles and fuel filters clog and kill the efficiency if not cleaned/replaced often. The whole idea of annual service for natural gas furnace is a lot of overkill. Most of it is just “checking” things. With an oil furnace there are physical things that need attention.
One last example of oil is diesel cars/trucks. That diesel is pretty much heating oil and fuel filters need to be replaced every 10K. At least that was the interval on my 2006 Chevy Duramax (a damn fine truck FWIW). Modern gas cars/trucks? Pretty sure the fuel filters are lifetime or at least a couple hundred thousand miles. Diesel/heating oil has a lot of impurities in it and is a different beast than natural gas/propane.
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Thank you…thats why I need to get out there in the feild with a good inspector already. Eager to learn.
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Based on your limited pictures, I would say it has a typical metal single wall vent, not PVC.
Probably some soot, and some dust.
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Yes, I was wrong It is a metal single-wall vent. There is a PVC pipe coming from the condensation pump. Wow, this section is so so hard.
It is unburnt oil. There is a sight glass above the gun where you can observe the flame. If it is dark yellow or looks sooty, the oil burner guy must fix it and check the flue temp and draft.
No, it is not a condensing furnace. Barometric dampers are installed only on boilers with negative venting. Boilers with pressurized vents would spill flue gases out of the barometric dampers into the room.
Old oil burners will backdraft until they get the flue up to temperature.
During cold startups, the cold stack may allow spillage of the flue gases into the boiler room until the stack warms enough to sustain draft.
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Ok…but there is an oil tank connected to the furnace here look at this.
Im goi g to get better pictures this week
So, if the furnace is 80% and metal flue the only condensation being generated would be from the A/C.
Curious too if anyone can confirm there are still no high-efficiency (90%+) oil furnaces? Google search seems to just lead to gas and some misleading terminology.
We’re you wanting to post a picture of the A coil?
I believe its above your response Larry. Was posting the attached AC unit connected to the Lenox furnace. Wow its that old.
I will get much better pictures tomorrow. Furnaces and HVAC is so darn complicated. However im really learning 
.
They claim 96.7% AFEU.
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