I have had my furnace worked on and cleaned (twice now), but there was
some junk
in the lines ( after oil delivery) so I ended up changing the nozzle
my self (after unit cut off a few times).
I had a few weeks of cleaning or changing nozzles, but it
seems to be running better now.
The unit calls for a 1.0 gph 80 degree type A, but I used a type W
because the guy at hardware store said it was ok to use.
Is this correct?
The problem I'm having now is that when the heat comes on and
the unit runs for a while, smoke is coming out near the chamber
somewhere.
Would the wrong nozzle cause this?
It is a delvan nozzle.

This is a Columbia Boiler with a becket burner.

Thanks for reading.