"mm" wrote
But I know, at least I think, some people have oil filters.




Something they might want extra money for it after they casually cause
me to think of it during the install? (Do you want the
rodent-protected air-intake?, for example.)

I've always had a filter and it is changed as a part of the normal service
on the burner. I'd think you have the potential need for it after 31 years
of accumulated sludge and whatever now than in the past.

When I got my new boiler, they also abandoned the old oil line that went
under the floor and went overhead. The air intake is rodent proof from the
factory.

If they are looking for extra money at the install, they are either
careless, sleazy, or both. As pros, they are supposed to think of all that
stuff up front.