A new damper design on select models of the company’s gas-fired water heaters enables the units to achieve an energy factor of 0.67 to 0.69, which meets Energy Star Phase II guidelines. When the gas control shuts off the fuel supply, it also signals a powered flue damper to close, reducing standby heat loss. Cost: $950 to $1,190. Rheem Manufacturing Co. 800-621-5622. www.rheem.com.