Wiring to add exhaust fan in bathroom
#1
10-31-05, 09:39 AM
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Wiring to add exhaust fan in bathroom
I want to add a exhaust fan/light combo in my bathroom. There is one wall switch that connects to a light fixture on the side wall over the sink.
The electrical is old knob/tube and there is only 2 wires going to the switch, very thick wires insulated in a cloth type material.
Can I tap into the switch for power, I have attic access and could probably locate where the wires drop down to the switch.
Thanks.
The electrical is old knob/tube and there is only 2 wires going to the switch, very thick wires insulated in a cloth type material.
Can I tap into the switch for power, I have attic access and could probably locate where the wires drop down to the switch.
Thanks.
#2
10-31-05, 10:13 AM
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No, you cannot tap into the switch for power. You need to tap power at the light fixture.
Let us know how you want to control this new fixture. Will the existing switch control it? Will you add one switch that will control both fan and light? Will you add two switches so that you can control them separately?
Then let us know all the wiring and connections at the existing light fixture.
Let us know how you want to control this new fixture. Will the existing switch control it? Will you add one switch that will control both fan and light? Will you add two switches so that you can control them separately?
Then let us know all the wiring and connections at the existing light fixture.
#3
10-31-05, 10:30 AM
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Whaever is the least difficult of these two options:
1) Control existing light, control fan/light combo independently - 2 control switch.
2) Control fan, control light, control existing light independent of others - 3 control switch.
1) Control existing light, control fan/light combo independently - 2 control switch.
2) Control fan, control light, control existing light independent of others - 3 control switch.
#4
10-31-05, 12:21 PM
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Fewer switches are easier than more switches, but both are possible. So you need at least one new switch. You have these options:
- Replace the single switch with a duplex switch and keep it in the same single-gang box.
- Expand the box to a double-gang box and install two single switches, or perhaps one single switch and a duplex switch.
- Expand the box to a triple-gang box and install three single switches.
- Install a triplex switch in the single-gang box (although this makes getting all the wires in the box very difficult).
- Replace the two wires between the existing light fixture and the switch box with a 3-wire cable. Then run a two-wire cable (for two switches) or a 3-wire cable (for three switches) from the switch box to the new fan/light combo.
- Add a two-wire cable from the existing light to the new fan/light combo. Then run a two-wire cable (for two switches) or a 3-wire cable (for three switches) from the new fan/light to the switches.
#5
10-31-05, 03:35 PM
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Ok. This is the option I will install:
Replace the single switch with a duplex switch and keep it in the same single-gang box.
If I do this are these the correct steps?
Replace the two wires between the existing light fixture and the switch box with a 3-wire cable. Then run a two-wire cable (for two switches) from the switch box to the new fan/light combo.
Add a two-wire cable from the existing light to the new fan/light combo. Then run a two-wire cable from the new fan/light to the switches.
Replace the single switch with a duplex switch and keep it in the same single-gang box.
If I do this are these the correct steps?
Replace the two wires between the existing light fixture and the switch box with a 3-wire cable. Then run a two-wire cable (for two switches) from the switch box to the new fan/light combo.
Add a two-wire cable from the existing light to the new fan/light combo. Then run a two-wire cable from the new fan/light to the switches.
#8
11-01-05, 10:20 AM
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We haven't gone over the connections yet, so post back with the connections you see now once you get it all opened up. For heavens sake, don't just disconnect everything without recording it and then come ask how to put it back together.
