I have an Aprilaire model 112 with manual humidistat control. I believe the wiring is incorrect. The unit will turn on regardless of whether the furnace is on or not. And from what I've read, the unit should only power up when the furnace or blower are on. But when I manually set only the blower on (regardless of the heat), the aprilaire will not turn on. Does anyone know where I can find wiring diagrams to help me figure this out. I just bought the house with unit already installed so I don't have any manuals. The manuals on aprilaire site that I can find only discuss the operation, not installation.