My baseboard heater in a bedroom quit working. I tried to replace it and the thermostat at the same time (both are 120v). Neither would work, so I tested my wires and this is what I got: ground to neutral- 121.7v, ground to hot- 121.7v, neutral to hot- .2
I'd be rather surprised if your electric baseboard is actually 120V - that's fairly uncommon. 240V is much more common, without a neutral in normal use (ground, L1 (black) L2 (white, which should be taped/re-colored red, but often isn't) and 240V between L1 and L2.
Whether the heater is actually 120V or 240V, the circuit is clearly in error if there is only 0.2V between white and black.