Hi There!

We just moved into a small, older (80 years?) apartment building and know very little about the wiring. I suspect some of it MIGHT be knob and tube, but I'm sure. Anyway, the light in the bathroom is on a dimmer that is on the wall outside the room. Inside the bathroom there is an outlet that is controlled by the dimmer switch which is no big deal, EXCEPT the outlet works in reverse to the overhead light. When the dimmer control (and the overhead light) is off, the outlet is receiving full power, and it drops as you turn up the dimmer until it is off when the light is on. Not great if my wife doesn't want to blow-dry her hair in the dark! I nosed around a bit in both the outlet and the switch and have found this: the box that the dimmer switch is in has one large, clothed-wrapped wire coming in the bottom and one coming in from the top. The dimmer has two wires coming from it and they are tethered to one of these wires each - which seems so far so good to me, this seems to be where the dimmer is interrupting the circuit to the light and controlling it. However, tethered in at these points are two wires which run to the outlet on the other side of the wall. So, in the box where the dimmer switch is we have two connection points, each with three wires in it. One has the wire coming up from below inside the wall, connected to one wire from the dimmer and another that runs off to the outlet. The other has the wire that also runs inside the wall but from above, the other wire in the dimmer and another wire that runs out to the outlet. At the outlet the two wires are attached where they would normally be (one black, one white). I suspect this is some sort of thing that a previous tenant rigged up, and I have tried switching the wires both at the outlet and at the dimmer, but it is still "reversed".

I hope I've made this sort of clear! Any help would be greatly appreciated, my first choice would be if the outlet was always on, but would be happy if it dimmed with the light!

Thanks so much!

What are you using plugged into the outlet to test how much it's dimming? Just the hair dryer, or have you tried, say, a 60 watt bulb? And if so, how does the bulb behave when you use the dimmer with the bathroom light off?

My guess is that the dimmer is wired to control only the light, but the outlet shares the same neutral and that there is an issue with that neutral. Trace both wires back from the outlet.

It is not safe to have a dimmer controlling an outlet AT ALL, especially if you will be using something like a hair dryer.

And if you're renting, why is your landlord not hiring an electrician to take care of this?

I actually have a multi-meter that I barely know how to use. I get a reading of 115.2 (volts?) when the dimmer is switched off, and that drops to 7.9 when the dimmer is on completely (dropping in sync with the dimmer being turned up). My wife and I are sure to use the outlet only when the switch is completely off, but obviously this is less than ideal. As far as my landlord goes, I have the great joy of living in a city with a less than 1% vacancy rate, so landlords tend to be less than eager to fix non-emergency problems! They'd probably just disconnect it, which I'd prefer not to have happen.

I've traced both wires back from the outlet, it's probably less than a foot, and they are the ones that are tied in at the dimmer switch box (one with the line coming in from the bottom and one dimmer wire, the other with the line coming in from the top and the other dimmer wire). Oh, this is so tough to describe! I made a diagram and will try to attach it.

Thanks!

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Wow, that's not wired right! With the dimmer off, the outlet should only partially work, and when it does the light should glow dimly. Either way it's not right.

Unforunately, assuming your wiring diagram is correct, you do not have enough wires to have the outlet working and safe. Your 'from below' is presumably a hot lead from the power source, the 'towards light' is presumably the hot lead to the light. The dimmer switch goes between them to control the light. In order for the outlet to work, you need an unswitched hot ('from below') and a neutral, which you don't have. I would disconnect the outlet, and get some 14-2, and run new wiring to it from the breaker box, or whatever other safe power source is nearby. If there is another outlet in the same area that would work too but I don't know if it would be up to code. TK can tell you more.

Yeah, I had feeling it was totally messed up! I'll root around and see if I can reach a nearby outlet, if not I might have to accept we won't have an outlet in the bathroom!

Thanks for your help!