Tell us about yourself!
My wife bought a professional $$ non-freeze waterer and it lasted about a year, she then bought the company's new and improved model to replace it. The second one is better sealed and does work well. I dissected the one that failed and it's just heat tape under the water tray with a thermal switch. I repaired the corroded connections and resealed it so it's working again. However, your idea is shear simplicity. If you added a thermal outlet (Farm Innovators TC-3) that kicks on at less than 35 deg. and off at 45 deg., you would have basically the same thing at a lot less cost. And we put our waterer up on bricks to keep it out of the dirt. So if you put a 12" x 12" paving stone under it I don't think the hens could tip it.