Bradford White Corp. has introduced a family of ultra high efficiency water heaters, the eF SERIES. These new water heaters boast thermal efficiencies of up to 99.1% and are capable of venting the equivalent of up to 120 feet using 3" or 170 feet using 4" ABS, PVC or CPVC piping. The eF SERIES units are available in 150,000, 199,999 and 250,000 Btus and feature the Hydrojet(R) Sediment Reduction System, Vitraglas(R) tank lining, glass coated flue tubes, magnesium anode rods and a brass drain valve. Bradford White Corp. Circle 1.