An oil burner control question

I had the pros put a new circulating pump on th eold oil burner a couple years ago. They put a new Honeywlll control box on the hot water jacket.
The module in the box is a block with three knobs, labeled Hi, Lo, and Diff.
I could guess, but is there a description of how to set this up for proper operation?
Right now I think I wantthe circulating pump to kick in sooner, but this is a general quesiton. The oil burner isn't used for domestic HW.
a d y k e s @ p a n i x . c o m
Harrison for Congress in NY 13CD
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