Flue condensate shield

Claim 1

An improved water heater comprising, in combination, a water heater tank having a vertical, open-ended flue formed by a cylindrical wall extending therethrough defining an inner wall of the tank adjacent water in the tank, said flue adapted to receive hot combustion gases for heating the water in said tank, a metal annulus having an outer side and an inner side formed at the bottom of the flue wall, said annulus being continuously affixed to and abutting the flue wall on the annulus outer side for effective heat transfer from the annulus to the flue wall and to water in said tank, said annulus having an upturned lip on the inner side thereof such that the annulus will collect and retain condensate forming on the flue wall for subsequent evaporation of said condensate, said annulus occupying from about 40 to about 60% of the sectional area of the flue and having a condensate holding capacity of about 0.3 cubic inch per 1,000 BTU/h of fuel input.