change light switch to operate exhaust fan and bathroom light independently

I am hoping to replace a single light switch that operates both my bathroom light and exhaust fan with a two-single pole switch so I can operate them independently.

I live in a dime a dozen town home in Las Vegas that was built less than 4 years ago. A friend lives in the same floor plan as me down the way and her bathroom has 2 separate light switches that operate the fan and lights separately, which leads me to believe that the wiring needed to separate the two devices is in the switch box rather than at the devices.

I did some research, and bought a two-single pole switch that fits in the original opening but can't seem to get the light to operate independently of the exhaust fan. Here's the wire situation...

Behind the switch plate, there seems to be three sets of wires, all sort of bundled together. Each wire bundle contains an exposed copper wire, a black and white wire. (so 9 wires are coming into the box). The 3 copper wires were connected with a wire connector to a 4th copper wire that was connected to the ground(green screw) of the original light switch. Of the black wires, 1 wire was connected to the original light switch directly, and the other 2 black wires were wire connected to a separate short black wire which was then attached to the original light switch as well. Finally, all of the white wires are wire connected together.

So how do I take the 3 wires that are were connected to the original light switch - the bare copper wire, the singular black wire and the bundled double black wire - and connect them to a dual single pole light switch, which has 4 screws for wires plus 1 ground/green wire screw? If I can get this to work, I;d like to repeat it on the other 2 rooms that have very loud exhaust fans that turn on when the bathroom light turns on. Please advise. Thank you.

Here are links to pictures I;veposted to assist in my explanation...


Picasa Web Albums - ItsAlyson

Picasa Web Albums - ItsAlyson

Picasa Web Albums - ItsAlyson

Picasa Web Albums - ItsAlyson

 

Turn off the power. Disconnect the black wires under the wire nut and connect one wire back to the pig tail going to the switch. Put a cap on the left over black wire and restore power. Turn the switch on and see what happens. If just the fan or just the light turn on, your in luck. If nothing happens, you not in luck and the only way it will work is to run a separate cable from the switch box to the fan or light.

 

Posted deleted. Tolyn presented an option I hadn't thought of.

 

So I connect the bare copper to the green screw, and pick 2 of the 3 black wires and connect them to either sides the double switch, leave the 3rd black wire capped off and leave the 3 white wires capped together? Then power back on and see if they operate independently?

 

This is a guess. The description sounds like a hot power cable from the breaker panel, a hot power cable going to a receptacle, and a cable to the light. If so, a two wire to the light will not work with two switches. A three wire will be necessary. Some testing would confirm this. What cables are in the ceiling box?

 

The exhaust fan is on a vaulted ceiling and I don't have a ladder tall enough to reach. Further info will have to wait until after Xmas. Thank you for the input.

It's looking like this job is more than I should bite off. Thinking I'll get an estimate to either have a dual switch installed or quieter fans installed by an electrician or just disconnect the power to the exhaust fan.

 

Not quite. Leave all wires connected to the existing switch.

Turn off power at breaker or fuse.

Undo the bundle of black wires.

Take the short wire (pigtail) of the bundle that is connected to the switch and reconnect it to one of the black wires of the same bundle you just disconnected. (basically all you did is remove one wire from the bundle)

Put a cap on the remaining wire for safety

Restore power and turn on switch. If only the fan or light turns on, you will be able to wire them separately with your new switch. If not, you will likely need an electrician.