The UB90-100 boiler has a 90-percent AFUE rating and is rated over 90 percent when used in low-temperature systems, such as radiant systems, the company says. The boiler has a cast aluminum heat exchanger, which transfers heat three times faster with greater thermal conductivity than conventional cast iron, claims the manufacturer. It draws fresh air from outdoors for combustion, instead of air from inside the home. With this design, the UB90 runs more quietly than a traditional boiler, the company claims. Features include a direct-vent system, premix gas burner, low flame temperature, integrated boiler control, high-temperature limit control, hot surface igniter, and single-stage gas valve.
Utica Boilers, P.O. Box 4729, Utica, NY 13504-4729; 315-797-1310; 315-797-3762 (fax); email@example.com; www.uticaboilers.com.