Do I understand correctly that your target is three classes, i.e., occupancy levels: 0, 1, and 2? Because this would have been my initial suggestion after reading the first sentence.
In general, though, this seems to be a very tricky task. Temperature and humidity are physical phenomena that generally change rather slowly over time – compared to a light or noise sensor, for example. With, say, a noise sensor, you probably wouldn’t even need a RNN.
Sorry, for not really helping here, but I would be curious if you could solve this. At the moment, I see principle limitations with this approach.