In Reply to: water tank heater watage posted by larryb on December 31, 2017 at 12:53:21:
1500 watts at 120 volt draws 12.5 amps. 12 ga is rated at 20 amps and 14 ga is rated at 15 amps. I wouldn't go over 100' with 14ga. With 12 ga you will have no problem. Most elements are rated for 120 and 240 volt. If you can run 240 volt your amperage cuts in half.