It's a 5 year-old Beckett oil burner with a 0.75 nozzle, if that matters.

what part of the country are you in? Does your oil burner create forced air heat? I bet its expensive heating with oil. If you have forced air, you should get an air sourced heatpump to handle the majority of your heating needs. The upfront cost will quickly be paid for by the oil savings.

Maybe the OP does have a heat pump... oil for backup. (That's the setup I have with no gas available and electric rate out of sight.)

Have to wonder if anyone knows the answer to his actual question.

This retired Navy Submariner loves the memories associated with diesel fumes and would not miss the opportunity to be present when the oil furnace is serviced. My nose tells me that #2 Heating oil is the same as diesel... just the color is not right. Again, however, I do not know the answer to hrajotte's question. :-)

Your furnace will love the Diesel fuel.

Fuel oil is not taxed. It is usually dyed red so that if it is used in an automobile/truck it will show up and the driver fined for using an untaxed fuel.

Some years ago they were different in that fuel oil was not low sulpher. But I think today that all suppliers provide the same ULS product for both fuel oil and vehicles.

The one thing that might be different is winterization. Around here, starting Nov 1 kerosene is mixed with road diesel to prevent freezing at low temperatures. It should still burn just fine with the fuel oil you have.

Yes, it is hot air, and yes, #2 is pushing $3.75 a gallon here in Massachusetts. Fortunately, we only have to turn it up late afternoon and early evening, as nobody is home during the day so we keep it around 55 degrees. Likewise at night, because the wife has about 6 blankets on the bed. We only use 300 to 400 gallons a year.
I figured diesel would be OK because I have seen heating oil being pumped into off-road construction equipment, such as excavators, at work sites.
Thanks all, we'll be pumping it in this weekend.
I agree with the Navy man, love the smell!!!