The LTB60-1LZ Leviton bathroom fan timer is an awesome addition to you bathroom. It would be really nice to add the ability to start it (or stop it) with the home automation as in my case, the fan and dimmed lights turn on when someone enters the room (who wants to be blinded when they have to go in the middle of the night?). It could also be triggered by temperature or humidity and there is no sacrifice of the manual timer functions.
There is a remote control wire that is designed to work with their Vizia+ Coordinating Remote Switch. The company would not reveal the technical information for designing your own remote switch input. So, the simple solution was to purchase a remote switch and disassemble it.
You add the remote feature by adding a simple Z-Wave relay with a 2K ohm 2 watt resistor from the remote wire of the timer (yellow/red wire) to the neutral (white wire in you box). I used the Qubino Z-Wave Plus Universal Relay with Dry Contact Switch ZMNHND3. Works like a charm with the addition of a temperature probe. An important note: make sure you program the switch auto off to 2 seconds or less. You don't want to leave it engaged for any longer.
I added a Zigbee SmartThings button near the commode just in case the timer runs out before you do.