I’m finding some unexpected behavior with my bathroom fan when using the blue 2-in-1 dimmer. When I turn on the fan at 100% the fan continually sputters but doesn’t start. However if I start it at a lower load like 35% for a second or two then it will start. Then I can increase to 100% and get up to max speed.
I suspect this is related to the mention about a max inductive load at Switch for a bathroom fan?. But it seems rather strange that it starts fine at a lower load?
The Blue 2-1 has not been tested nor approved by the UL for motor ie inductive loads and AFAIK, the dimmer function is not designed for or rated for such loads.
The thread that you linked pertains to the Red switch (not Dimmer) which is rated for inductive loads but since it is a switch, will not vary the fan speed. There is a zigbee fan switch under development which will likely be suitable for your application, but the Blue 2-1 is not.