Very basic electrical question. I have a non-functioning double pole thermostat (wired to an electric baseboard). I'd like to replace it, but of course my breakers are not labeled. Is there any way to use a simple voltage tester to identify the circuit? (Or, does the fact that there's no neutral wire mean that you can't find a voltage drop? (Thinking back a few decades to Physics 101)) If not, what can I do?
A simple voltage tester would work fine, you can test line to line and get 240v or line to ground to get 120v. Lack of voltage drop would only matter if you tested line to load when load is open. Even a non-contact sensor should work fine for determining voltage being present. You could also turn off all two-pole breakers.