Rev. Rul. 54-386

The tax imposed by section 3406(a)(3) of the Internal Revenue Code of 1939 on electric water heaters is limited in application to heaters of the household type. An electric water heater with heating elements aggregating wattages not exceeding 7500 (7 1/2 KW) is a heater of the household type and the sale of such a heater by the manufacturer is subject to tax imposed by that section of the Code unless the heater by reason of other features of design and construction is primarily adapted for purposes other than household use.