My parents have 3 baseboard heaters, run by one thermostat, that were original in 1971. All three heaters have stopped working at different times, the last one last Spring. (This is the one they asked me to replace.) At the time I got a good voltage reading from the black wire, and the new unit worked fine, but after 3 days, it stopped working. The new baseboard unit still has continuity, but from the wire in the wall, I now get 17 volts from the neutral (white) wire only. I checked at the other two baseboards, and one gets 8 volts, and one 43, again both just from the neutral wires, with nothing from the power (black). What am I probably looking at? (The 2 times I've run into a situation like this before, the problems were a ground fault in 1, and bad wire in the 2nd. The bit of advise I've gotten so far is to start looking at the thermostat, checking the power there.)