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BillyHvac, Journeyman HVAC Tech
Category: HVAC
Satisfied Customers: 21997
Experience:  Endorsed for unlimited heating, cooling, oil burners, boilers, refrigeration, hydronics
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Oil Burner Settings. Hot air furnace. Test for ignition coil

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Oil Burner Settings. Hot air furnace. Test for ignition coil? Spark gap setting in side and location related to nozzle. How to adjust air inlet opening. Setting for "eye" on bottom of ignition transformer. 3 months past "burner man" checked it all. Had to replace nozzel already 2 days ago. Was smelling furnace when it started. "Eye" was dirty again in 3 months. New nozzel and cleaned eye. Opened the air inlet on burner some. Furnace runs for ok but goes off on reset still once and a while. Runs ok for 12 hrs or so after reset. Something must still be not set right. Had a new ignition coil in the last few years. Becket burner. I am a ind. electrician/electric motor mechanic.

Have you pulled the draw assembly recently?



Customer: replied 7 years ago.
Ok you will have to use discriptive terms rather then burner part names. Some diagrams showing parts locations and tech names would help. Do you mean the assembly with the oil feed tube electrodes for the spark and nozzle ? If so yes I replaces the nozzle a few days ago.

OK, here are the basics for a Beckett-


electrodes 1/8" gap at center point, 1/8" forward from nozzle face, 1/2" up from nozzle center orifice.


Barometric damper. If you are getting a dirty fire eye, you may be under positive pressure. Breech draft 2wc and stack draft 4wc.


Transformer spark test. turn off oil and start unit, flip transformer up carefully. The 2 springs are capable of 10,000 volts. Take an insulated screw driver and hold post to post to make spark jump. Spark should jump at least 1/2" to an inch. BE CAREFUL.


Oil pump pressure should be 100psi.


air adjusted to bright yellow flame orange/smokey not good. This not a tuneup but should get you close.


Let me know if you have any more questions.




Customer: replied 7 years ago.
Ok sounds like the last "expert" missed the location of the electrodes. Hard to find a good burner man here, even though you need a licence to be one. Even to install a tank now, you cant even purchace a tank in Nova Scotia without a licence. Even if you want to store apple juice in it(not that I would).
Ok I will check that over tomorrow. Can I send a picture on this site? I am going to get one of the electrodes before I move them. The furnace location has lots of air from outside, I think I know what you mean by positive pressure can you explain a situation causing that?

Yes, the barometric damper controls how fas the heat/exhausts gets up and out of the furnace and vent pipe. When the unit is running and the damper is flapping open it slows the draw from the furnace by pulling air through the damper. Like a hole in a straw. This is an efficiency balance. We want to keep the heat from racing up the chimney and not get our moneys worth of heat. But, this if not balanced right, can slow the draft to where the furnace is postive instead of negative. If you opened the inspection door, you should be able to hold smoke in front of it and see it suck into the furnace, when it is positive it blows back. Thus when I see a dirty eye, I wonder why the soot came back to the transformer.


I believe your issue will be electrode settings, air mix, and damper setting. A good oil man can set the draft , pressure, use a correct nozzle and really obtain a pretty efficient burn.

By all means, let me know if you have more questions. If you cant tell I like to ramble a bit about the units.



Customer: replied 7 years ago.
So if the damper door opens way up there isnt enough pull in the firebox and the smoke feeds back? When I opened the inspection door I sometimes get smoke. On a normal day how much should it open? Roughly
Customer: replied 7 years ago.
It quit about 130 am last night so I didn’t get a picture. It seemed hard to adjust the electrodes in front of the nozzle and keep the 1/8 gap. Do they burn away over time? The furnace is about 10-15 years old although the last guy said the metal all looked good as far as it leaking carbon monoxide was concerned. Also I assume the damper pivot points should be set level, the furnace is in a crawl space set on its side and the pipe goes away at a shallow angle to the chimney. I will try to make it swing better as it catches closed at times.
I adjusted the air back to a little more closed to where it was originally, wow it doesnt take alot of air to get a bright yellow flame.



The electrodes could possibly wear over time but is unlikely. I work on units with 30 yr old points that are fine. The damper should be level and able to swing freely, but without a draft gauge we wont know what to set the counter weight for. If the unit is blowing exhaust out of the inspection door, we want to adjust that damper so it does not open as much so we can force the draft a bit.


The air mix is critical in the process for the unit not to soot up. Sounds like you are getting closer.



Customer: replied 7 years ago.
Thats great. Thanks for the help. Anything else I should be aware of? How do you deal with a flooded furnace if its been restarted with out lighting a few times? Shut the oil off and let it time out a few times?

That one made me smile....Because I happen to have some experience with flooded oil boilers.....Some stories are better left unsaid.


Throw some lit newspaper in there and have something to prop open the inspection plate. I saw one get so pressurized one time it blew off the barometric damper.


Be careful, and remember, if possible it is best to get it set right with pressure gauges, draft test, smoke test, co test etc.


But this should get you by.


Good luck,



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