A Furnance Question

[tp]

Hi Group

Could I correctly assume, that the following data shown on my furnance indicate its 80% efficiency ?

Make: Anthes Model: LN 140 HAAAA Burner Input: 140,000 Btu/hr Bonnet Output: 112,000 Btu/hr Year: not provided

Does anybody have a clue, how old this unit could be ?

Regards Tad

[TURTLE]

This is Turtle.

Most all date codes are in the Serial number. Try to find it.

I have not heard of Athes but of cource they dream up a new name or brand every nite.

TURTLE

[Bill]

No, my 29 year old Lennox has the same ratio but is only about 60% AFUE. That is steady state output not taking into account start stop cycles, flue draft waste etc