Steve Barker wrote:

That "store bought" fuel may not wanna flow when it's 20 below. Heating
oil is straight #1 diesel.

Heating oil is #2 diesel, not #1 (Kerosene). I have 34 years of
experience with oil heat to confirm that.

You won't find that at the pump.

Yes, actually you will. Kerosene #1 pumps are relatively common.

And the
mix you do find at the pump will not burn as hot and may cost you by
using more and causing excessive build ups in the furnace.

Sorry, you are entirely incorrect. #2 fuel oil and #2 diesel are exactly
the same other than the red dye and taxes, #1 kerosene is always the
same and has a little less BTU content per gal then #2, but that's about
it. None of them will cause any sort of buildup any different than your
normal heating oil.