The white wire is wrapped with black tape to identify it as hot. The black wire connects the fan to the speed controller. The red wire connects the light to the dimmer.
This wiring arrangement allows for lowering the lights with a dimmer and controlling the fan with the builtin pull chain. The source is at the ceiling outlet box and 3-wire cable runs from there to the switch box. The neutral from the source is spliced directly to the white wire on the fan kit and the cable, running it through to the switch box.
In this arrangement a light fixture and exhaust fan are wired to the same source. The light is controlled with a single-pole switch and the fan controlled with a timer as in the previous drawing. The hot source is spliced to each controlling device and the output of the controllers are connected as in the previous diagrams on this page.
In this wiring, the source is at the switch and 3-wire cable runs from there to the fan/light. The switch controls the light and the source is spliced through to the fan. With this arrangement, the fan is controlled by a pull-chain on the motor housing and the light is controlled with the switch. The neutral and ground wires are also spliced through to the fan/light.