What do the dots in the electrical water heater stand for?

Question:Hi, i moved into this apartment and it has an electric water heater in the bathroom. It only has a knob at this switches to one dot or two dots. I'm assuming this isn't an on-of control... then what do the dots mean? Hi-Lo? Switching it to one dot will reduce energy consumption?

Thanks

J

Answers:
I don't know for sure, but the switch may control the temperature. The water heater may have two thermostats, and the switch selects which thermostat is to be used.

It's easy to check this out. Set the water heater to one dot and allow the temperature to stabilize overnight. First thing in the morning, measure the maximum temperature you can get out of the bathroom faucet using a meat thermometer. Repeat the following night, but with the water heater set to two dots. If my theory is right, two dots is hotter than one dot.