I have a 12/2 (black/white/ground) power source to the leviton 1755 switch. And, I have two (2) 12/2's going to a Broan 100hl (vent, light, heater). Please help wiring switch and Broan; on Broan, red/white wire = heater, black/blue/white = light and vent. Thanks!

The switch that you have works like 3 seperate switches. most of these switches will have gold screws
on one side and silver screws on the other side, lets say that the left is gold and the right is silver, and
the switch may also have a green screw for ground. your 12/2 with ground is your main hot, you may
want to mark it with a piece of tape, so you know it's the incoming hot. the ground off your hot will tie,
to the green screw on switch and continue and tie to your vent light which should also have a ground
the white coming off the hot is your neutral, it will go straight to your white or whites on your heater.
the black hot wire at your switch will go to each gold terminal on one side of the switch,there are two
ways you can do this, go to one side and just run a jumper, or put one wire on each gold screw and
tie in to your hot-black wire with a wire nut. now for the switch legs, you will need to run from your, switch
to your heater either another pair of 12/2s or a 12/3, each side of the switch that has one silver screw,
it's easier with a 12/3 normally a 12/3 will have a red,black,white,and ground.
top switch red to red on heater,black to black on light and the white blue on the vent,so from your switch
to the heater you would have to run a12/2 you would not use the black only the white and ground.
remember the white-neutral coming from the switch will be tied to all the whites at the vent,light,heater
except for the 10/3. the 10/3 is used stricktly for the switch legs. good luck!

Power source is black and white.
Black hot and White neutral.
Black hot wire connects to dark screw on switch.
Other side of switch has 3 brass screws.
Connect 1-black-light wire, 1-blue-fan wire, 1-red-heater wire to each of the 3 brass screws. So 3 wires going to Broan are each connected to different brass screw.
That leaves 1 extra wire going to Broan.
Connect extra wire going to Broan to the White neutral.

Light, fan and heater have two wires each. Light fan and heater are connected to switch with one wire each. Take second wire from each light, fan, heater and twist all three of these wires together and connect to extra wire going to Broan.
So each light fan and heater have 1 wire connected to switch and 1 wire connected to neutral.