Oil Furnace Short Cycling, Honeywell R7284 Control

[fbelec]

You mean to disconnect the T-stat connection and put a jumper across the terminals?

yes

does you furnace have this control
if so take off the cover and watch it se if it moves right. watch it from cold. pull it out and look at it see if there is and buildup on it.

https://www.homedepot.com/p/Honeywe...gclsrc=aw.ds&dclid=CIiSvfed_NcCFQSnyAodxkoEZg

 

[JRP3]

yes

does you furnace have this control

No, doesn't have that. The furnace is this unit https://www.lennoxpros.com/of23q34-105120-furn-oil120kb3-4ton/p/26K75
This is what it looks like in the burner area

 

[begreen]

Unfortunately Lennox does not make it's manuals and schematics easily available.
Is the blower coming on a little bit after the furnace comes on?
Has the filter been checked?
Has the burner photocell been checked to see if it is dirty?
Is there a low fire pressure switch in the system and if yes, has it been checked?

 

[Hogwildz]

If it is cutting off before the blower fan kicks on, I'd bet it is the high temp limiter.

 

[JRP3]

When the furnace first fires up the burner runs, then the fan comes on, and the fan stays running as the burner cycles on and off, until temperature is reached. The cad cell readout hovers around 200 ohms when running, which is the normal range from what I can tell.
By filter do you mean the air filter or oil filter? I looked at the air filter today and it seems to be clean. I don't know about a low fire pressure switch.
I did take the cover off that covers the circuit board and noticed some slight burning on the board near a ceramic resistor. I think after the weekend I'm just going to call the pros and let them deal with it.