On Tue, 27 Jan 2015 14:45:26 -0800 (PST), wrote:

I have a 2001 Burnham V8(oil burner hot water) with energy
efficiency between 78-80%. Is that good for its age?

I know more about oil than gas.

When I divide the output BTU's*** by the input BTU's on my 1979 Carreir
oil furnace (hot air), I get about 80%. ***As listed in the owner's
manual that came with the furnace, and is online too.

When I was shopping for a new furnace a couple years ago, the efficiency
of all of them** was about 82%. (iirc but at any rate, little higher
than my furnace rating.)

People here at the time did not believe me that the efficiency has gone
up so little.

Are you somehow giving the measured efficiency or the rated one?
Anyone know if there is an innate difference in the efficiency of hot
air furnace vs. a hot water furnace?

** (except some special kind that is very expensive, not so often
advertised or even mentioned, and very few buy (whose design name I
forget. Retroactive, incandescent, self-descending, or something.).)