The FTC charged three firms with false advertising.

False-advertising charges were brought against three companies promoting “duty cycler” devices designed to save energy. Claims that duty cyclers could save consumers from 15% to 40% on their heating and air-conditioning bills--and would pay for themselves in 18 to 24 months--are false and unproven, the FTC charged. Duty cyclers cause heating and air-conditioning units to cycle on and off more frequently and keep the blower fan running in an attempt to make the unit work more efficiently, the commission said. Named in the civil complaints were Electronic Systems International, Electro Tech Manufacturing and National Energy Associates, all of Norcross, Ga.