Rinnai’s Ultra Series condensing tankless water heater has an energy factor of .96. The secondary heat exchanger is at the bottom so condensate can’t leak onto other components. “We’re following the boiler world, which uses this design for long-term reliability,” the product manager told us. Since the Ultra’s logic circuit can be wired to a recirculating pump, the pump and heater run only when the loop needs to be warmed. Cost: $1,830.
Rinnai, 800/621-9419, rinnai.us.