How do I replace a light switch to a dimmable switch?

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moi
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How do I replace a light switch to a dimmable switch?

Post by moi »

I am planning to replace a light switch to a dimmable light switch.

It's too small of a job to get the electrician to even show up, so I'm trying to do it myself. I'm hoping that some of the knowledgeable folks here could help me out.

Background:
1) ceiling canned light - the retrofit LED light is verified dimmable
2) This is a single pole light switch
3) The box is a single switch box. This looks like a plastic, not metal box
4) There are two cables coming into the box. The cable is white. Each cable has three wires: a black, a white, and a bare copper. I measured the wire with a stripper and confirmed this is a solid 14 guage copper wire.

Current setup:
1) When I pull out the single light switch, there are only two black wires connected to the light switch. That's it. One black wires comes from one cable, and the other black wire come from the other black cable. The current light switch does NOT have a ground wire.
2) The two white wires (the neutral) from the two cables are connected inside the box.
3) the two bare copper wires (the ground) from the two cables are connected.

Image

The replacement dimmable switch:
-Lutron LED+ dimmer switch from home depot. This one could be set up as a single pole or a three way switch. There are four wires coming out of this switch: one black, one red, one red/white stripe, and one green (ground).

I included a link to the product below
https://www.homedepot.com/p/Lutron-Diva ... 70#overlay

-------------------------------------------------------
To set this one up as a single pole switch, the black wire and the red wire from the dimmable switch are to be connected to the two black wires currently connected to the existing switch, easy enough.

The red/white stripe wire unused wire from the dimmable switch is supposed to be capped off with a blue connector.

I've included the link to the walk-through installation guide below:

https://webtools.lutron.com/wiringwizar ... 71:a87,r73

--------------------------------------------------------
First Question:
I'm confused by ground wire. How come the existing switch does NOT have a ground wire connected? Is that dangerous?

According to the installation manual of the new dimmable switch, the new switch's green wire is supposed to be connected to the ground. However, because there isn't a ground connecting to the existing switch, do I simply NOT connect a ground to the new dimmer switch's green wire?

Inside the box, I see that the two cables comining in each have a bare copper cable, which I understand is the ground. They are connected together. Am I supposed to do something with those two bare copper wires? Or leave them alone? The current switch does not connect to those two copper wires directly.

When I used the walk through tutorial for the dimmer installation, there is an option to click that says "I do not have a ground in my wallbox." After I click it, it says:

No ground? No problem! Don't have a ground wire? The NEC syas this is fine as long as a nonmetallic, noncombustible faceplace is used with nonmetallic attachment screws.

The current light switch faceplate is plastic, and the screw to screw the faceplate to the light switch is painted (which I presume provides insulation to make the screw a non-conductor). Does this mean it's okay to not have the ground wire attached to the new dimmable switch?

And yes I did turn off the breaker in the electrical panel before I started working on the light switch.

Second question:
On the current switch, when the switch is screwed into the box, I noticed there is a tiny piece of thin cardboard paper between the switch and the hole on the box. In the picture below, that piece of thin cardboard paper is on the screw. What's the purpose of that paper?

Image

Third question:
Do I use a yellow connector to connect the dimmable switch wire to the black wire coming from the box? The black wires are 14 gauge solid copper wires. The dimmable switch are 18 gauge stranded wires, and they look "silver" not copper. The yellow connectors (wire nut) chart says it could connect (1-2) 14 AWG & (1) 18 AWG. I interpret that as connect one or two 14 gauge and one 18 gauge wires are permitted using the yellow connector. Is that right? However, the manual also says, wire connectors provided are suitable for copper wire only. For aluminum wire, consult an electrition. Since the wire coming from the dimmer switch looks silver, does that mean it's something other than copper? So does that mean I cannot sue the yellow connector in this circumstance?

Appreciate everyone's input.
Best, | moi
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galawdawg
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Re: How do I replace a light switch to a dimmable switch?

Post by galawdawg »

moi wrote: Sun Jan 16, 2022 3:00 am I am planning to replace a light switch to a dimmable light switch.

--------------------------------------------------------
First Question:
I'm confused by ground wire. How come the existing switch does NOT have a ground wire connected? Is that dangerous? Most existing dimmer switches (and light switches in general) do not have a ground wire. They simply interrupt the electricity through the "hot" wire (black). Don't worry about it.

According to the installation manual of the new dimmable switch, the new switch's green wire is supposed to be connected to the ground. However, because there isn't a ground connecting to the existing switch, do I simply NOT connect a ground to the new dimmer switch's green wire? No. Connect the green wire on the new dimmer switch to the ground wires of the circuit (the bare copper wires that are twisted together and folded in the back of your electrical box. You may need to make a "pigtail" to make the connection to those ground wires.

Inside the box, I see that the two cables comining in each have a bare copper cable, which I understand is the ground. They are connected together. Am I supposed to do something with those two bare copper wires? Or leave them alone? The current switch does not connect to those two copper wires directly. The green wire on the new dimmer switch will connect to those....see above.

When I used the walk through tutorial for the dimmer installation, there is an option to click that says "I do not have a ground in my wallbox." After I click it, it says: No ground? No problem! Don't have a ground wire? The NEC syas this is fine as long as a nonmetallic, noncombustible faceplace is used with nonmetallic attachment screws. The current light switch faceplate is plastic, and the screw to screw the faceplate to the light switch is painted (which I presume provides insulation to make the screw a non-conductor). Does this mean it's okay to not have the ground wire attached to the new dimmable switch? Ignore all of this, you do have a ground in your wallbox.

And yes I did turn off the breaker in the electrical panel before I started working on the light switch. Good. Also, be sure to use a tester to ensure all of the wires in the box have no current.

Second question:
On the current switch, when the switch is screwed into the box, I noticed there is a tiny piece of thin cardboard paper between the switch and the hole on the box. In the picture below, that piece of thin cardboard paper is on the screw. What's the purpose of that paper? It simply keeps the screw from falling out of the switch. No problem if the cardboard isn't there. Just don't lose the screw(s). :happy

Third question:
Do I use a yellow connector to connect the dimmable switch wire to the black wire coming from the box? The black wires are 14 gauge solid copper wires. The dimmable switch are 18 gauge stranded wires, and they look "silver" not copper. The yellow connectors (wire nut) chart says it could connect (1-2) 14 AWG & (1) 18 AWG. I interpret that as connect one or two 14 gauge and one 18 gauge wires are permitted using the yellow connector. Is that right? However, the manual also says, wire connectors provided are suitable for copper wire only. For aluminum wire, consult an electrition. Since the wire coming from the dimmer switch looks silver, does that mean it's something other than copper? So does that mean I cannot sue the yellow connector in this circumstance? The switch wires are not aluminum, they are stranded copper with a tinned coating to keep them from fraying or untwisting. Just use the wire connectors that Lutron provided with the switch.
Answers in red above. Hope that helps.
jharkin
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Re: How do I replace a light switch to a dimmable switch?

Post by jharkin »

You got generally good advice above, but I would like to add one clarification.

By code, the ground wire *should* have been connected to the ground post of the original switch. The ground in an AC system is a safety measure, connecting the metal shell of that switch to ground so that just in case it ever shorted internal the electricity would have a path to ground that doesn’t go through you.

Sometimes a lazy DIYer leaves it off,and 99.99% of the time it will never be needed but in that 0.01% it is it may save a life.
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galawdawg
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Re: How do I replace a light switch to a dimmable switch?

Post by galawdawg »

jharkin wrote: Sun Jan 16, 2022 6:24 am You got generally good advice above, but I would like to add one clarification.

By code, the ground wire *should* have been connected to the ground post of the original switch. The ground in an AC system is a safety measure, connecting the metal shell of that switch to ground so that just in case it ever shorted internal the electricity would have a path to ground that doesn’t go through you.

Sometimes a lazy DIYer leaves it off,and 99.99% of the time it will never be needed but in that 0.01% it is it may save a life.
To put a finer point on the clarification, I believe that NEC did not require grounding of switches until the 1999 revision. (NEC 380-9, 1999).

So it wouldn't be unusual at all for any dwelling constructed prior to 1999 to have ungrounded light switches, even when properly wired according to code by a licensed electrician and inspected properly by the local governing authority.

:beer
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Re: How do I replace a light switch to a dimmable switch?

Post by Sandtrap »

RE: Differentiating which "black" is the load and which "black" is the "hot/feed" is important.

j :D
Last edited by Sandtrap on Mon Jan 17, 2022 6:29 am, edited 3 times in total.
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McDougal
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Re: How do I replace a light switch to a dimmable switch?

Post by McDougal »

Hmmm. Now you've got me thinking. A dimmer switch in a bathroom. Huh.
dbr
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Re: How do I replace a light switch to a dimmable switch?

Post by dbr »

McDougal wrote: Sun Jan 16, 2022 8:51 am Hmmm. Now you've got me thinking. A dimmer switch in a bathroom. Huh.
My bathroom has an exhaust fan also housing two bulbs. One is a full ceiling light and the other is a night light. There are separate switches inside the door. If the bathroom has only one socket a person might want to leave it on dim or use it on dim at night.
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Re: How do I replace a light switch to a dimmable switch?

Post by McDougal »

dbr wrote: Sun Jan 16, 2022 9:10 am
McDougal wrote: Sun Jan 16, 2022 8:51 am Hmmm. Now you've got me thinking. A dimmer switch in a bathroom. Huh.
My bathroom has an exhaust fan also housing two bulbs. One is a full ceiling light and the other is a night light. There are separate switches inside the door. If the bathroom has only one socket a person might want to leave it on dim or use it on dim at night.
Yeah, I get it, there are probably other reasons too, I just never considered it. The more you know!
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quantAndHold
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Re: How do I replace a light switch to a dimmable switch?

Post by quantAndHold »

We had our main bathroom remodeled in 2020. The electrician put in dimmer switches for all the lights without asking. I would have never thought to ask, but surprisingly, we use the dimmers a lot.

OP, if you’re not comfortable doing this, you don’t need an electrician. It’s something a handyman could do.
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Bogle7
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Re: How do I replace a light switch to a dimmable switch?

Post by Bogle7 »

Step 0: Make sure your insurance policies are up to date.
Step 1: YouTube
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Old fart who does three index stock funds, baby.
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walkabout
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Re: How do I replace a light switch to a dimmable switch?

Post by walkabout »

This probably doesn’t apply in your situation, but make sure that there is not an electrical outlet downstream of the switch.
michaelingp
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Re: How do I replace a light switch to a dimmable switch?

Post by michaelingp »

Sandtrap wrote: Sun Jan 16, 2022 8:23 am One of the black wires is the "feed" so it's completely black and attached to the "brass" colored screw connector on the existing switch.
The other "black wire" should have white tape around it since it is the "load" return wire. It is attached to the "silver" colored screw connector on the existing switch.
Not to be harsh, but this is completely wrong. A normal (single pole) switch will have two brass colored screws, and both are "hot" and interchangeable. You should never see a white wire on a normal switch (or a silver-colored screw), just red and blacks. The wires in the OP picture have some white drywall mud (or maybe paint) on them, but they are clearly black wires. There may be some exceptions to this (like switches with pilot lights in them), but you will not normally see a white wire on a normal single pole switch.
rgs92
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Re: How do I replace a light switch to a dimmable switch?

Post by rgs92 »

I prefer those new LED lamps that are rechargeable. They are all dimmable (and some even have changeable light colors, and some I think have remote controls), and they are safe to use and pretty cheap ($30- $50 on Amazon). Just buy a bunch of them. I use them everywhere now.

No electrical work needed, and they can be around water. I love these things.

https://www.amazon.com/Biilaflor-Portab ... 4585113206
Running Bum
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Re: How do I replace a light switch to a dimmable switch?

Post by Running Bum »

An LED smart bulb is a lot simpler than digging into uncertain wiring. Control it with your phone or an Echo Dot or Echo Flex or similar. On/off, dim, different colors, and different warmth levels of white.
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Re: How do I replace a light switch to a dimmable switch?

Post by Sandtrap »

michaelingp wrote: Sun Jan 16, 2022 3:35 pm
Sandtrap wrote: Sun Jan 16, 2022 8:23 am One of the black wires is the "feed" so it's completely black and attached to the "brass" colored screw connector on the existing switch.
The other "black wire" should have white tape around it since it is the "load" return wire. It is attached to the "silver" colored screw connector on the existing switch.
Not to be harsh, but this is completely wrong. A normal (single pole) switch will have two brass colored screws, and both are "hot" and interchangeable. You should never see a white wire on a normal switch (or a silver-colored screw), just red and blacks. The wires in the OP picture have some white drywall mud (or maybe paint) on them, but they are clearly black wires. There may be some exceptions to this (like switches with pilot lights in them), but you will not normally see a white wire on a normal single pole switch.
You are correct.
I was thinking of another type of switch that I just put in where it was important to differentiate between which "black" is the "load" and which "black" is the "hot/feed".
Sometimes electricians will put a single wrap of white tape to show which wire it the "load" (to the light). On some switches, this is important. The last 8 dimmers that I installed in my own home were like this.

Good catch. :sharebeer
Thanks!
j :D
Last edited by Sandtrap on Mon Jan 17, 2022 6:32 am, edited 2 times in total.
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rgs92
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Re: How do I replace a light switch to a dimmable switch?

Post by rgs92 »

Running Bum wrote: Sun Jan 16, 2022 3:49 pm An LED smart bulb is a lot simpler than digging into uncertain wiring. Control it with your phone or an Echo Dot or Echo Flex or similar. On/off, dim, different colors, and different warmth levels of white.
Great idea. LED lighting is a godsend.
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Re: How do I replace a light switch to a dimmable switch?

Post by suemarkp »

You can have a white wire when there are only two wires in the box (a switch loop), but you don't have that here fortunately. But Sandtrap did mention one thing that may be important. You need to know which black wire is the power source and which black wire goes to the light. The black power source wire goes to the black on the dimmer switch. The black that goes to the light goes to the red on the dimmer switch. Get them backwards and hopefully it just doesn't work. Worst case, you fry the dimmer.

You need a meter or a non contact voltage tester to determine this. With the black wires disconnected from the switch, hanging out of the box, and the live ends capped off, turn on the circuit breaker and bring the non contact tester near each black wire. The power source wire should set it off. The one going to the light should not. Remember which of the two was the power source wire, turn off the breaker, test it again with the non contact tester to make sure it is dead now, and then connect it to the black wire of the dimmer. Then connect the other wires on the dimmer.

By the way, if your house was built before 1993, or before the 1993 national electric code was in effect, switches were not required to be grounded unless they had metal faceplates (metal screws with plastic plates were OK then on ungrounded switches inside).
Mark | Somewhere in WA State
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moi
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Re: How do I replace a light switch to a dimmable switch?

Post by moi »

jharkin wrote: Sun Jan 16, 2022 6:24 am You got generally good advice above, but I would like to add one clarification.

By code, the ground wire *should* have been connected to the ground post of the original switch. The ground in an AC system is a safety measure, connecting the metal shell of that switch to ground so that just in case it ever shorted internal the electricity would have a path to ground that doesn’t go through you.

Sometimes a lazy DIYer leaves it off,and 99.99% of the time it will never be needed but in that 0.01% it is it may save a life.
Got it! Makes sense. Thanks
Best, | moi
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moi
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Re: How do I replace a light switch to a dimmable switch?

Post by moi »

quantAndHold wrote: Sun Jan 16, 2022 9:51 am We had our main bathroom remodeled in 2020. The electrician put in dimmer switches for all the lights without asking. I would have never thought to ask, but surprisingly, we use the dimmers a lot.

OP, if you’re not comfortable doing this, you don’t need an electrician. It’s something a handyman could do.
Even a handyman is hard to come by these days. I once paid one $200-$300 bucks to put weather-stripping around one door, and I provided the weather-strip, and he dropped and lost some screws that came with the kit, and the miter wasn't good at all. I only got him because he's the one that would even show up, and I guess the reason is that he charges way too much and doesn't even do that great of work. Argh.
Best, | moi
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moi
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Re: How do I replace a light switch to a dimmable switch?

Post by moi »

michaelingp wrote: Sun Jan 16, 2022 3:35 pm
Sandtrap wrote: Sun Jan 16, 2022 8:23 am One of the black wires is the "feed" so it's completely black and attached to the "brass" colored screw connector on the existing switch.
The other "black wire" should have white tape around it since it is the "load" return wire. It is attached to the "silver" colored screw connector on the existing switch.
Not to be harsh, but this is completely wrong. A normal (single pole) switch will have two brass colored screws, and both are "hot" and interchangeable. You should never see a white wire on a normal switch (or a silver-colored screw), just red and blacks. The wires in the OP picture have some white drywall mud (or maybe paint) on them, but they are clearly black wires. There may be some exceptions to this (like switches with pilot lights in them), but you will not normally see a white wire on a normal single pole switch.
That is correct. The black wire have white tips due to drywall mud. I could scratch them off. I made sure isn't not somehow taped white for some reason. There are two white wires that are twisted together with a wire nut.
Best, | moi
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moi
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Re: How do I replace a light switch to a dimmable switch?

Post by moi »

suemarkp wrote: Sun Jan 16, 2022 3:57 pm You can have a white wire when there are only two wires in the box (a switch loop), but you don't have that here fortunately. But Sandtrap did mention one thing that may be important. You need to know which black wire is the power source and which black wire goes to the light. The black power source wire goes to the black on the dimmer switch. The black that goes to the light goes to the red on the dimmer switch. Get them backwards and hopefully it just doesn't work. Worst case, you fry the dimmer.

You need a meter or a non contact voltage tester to determine this. With the black wires disconnected from the switch, hanging out of the box, and the live ends capped off, turn on the circuit breaker and bring the non contact tester near each black wire. The power source wire should set it off. The one going to the light should not. Remember which of the two was the power source wire, turn off the breaker, test it again with the non contact tester to make sure it is dead now, and then connect it to the black wire of the dimmer. Then connect the other wires on the dimmer.

By the way, if your house was built before 1993, or before the 1993 national electric code was in effect, switches were not required to be grounded unless they had metal faceplates (metal screws with plastic plates were OK then on ungrounded switches inside).
You know I thought about which of the black wire is upstream (from the power source) and which of the black wire is downstream (sends power to the light), but the installation instructions didn't seem to care which is which, as long as one is connected to the black and one is connected to the red.
Best, | moi
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moi
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Re: How do I replace a light switch to a dimmable switch?

Post by moi »

Okay all. I need a little more help here.

I'm pretty sure I did this correctly (see photo below)

One black from the box to one black from the dimmer switch.

One black from the box to one red from the dimmer switch.

The red/white stripe from the dimmer is not used and capped off with blue wire nut.

The green ground wire from the switch is twisted into two bare copper wires as in a pigtail (pretty sure that's what I did)

I turned the switch on and off and NOTHING happens. Even if I turn the dimmer to the brightest.

Did I get a brand new broken switch? Or did I do something wrong? Using Lutron's instruction, I'm pretty sure it doesn't matter which black wire from the box I use to connect to the dimmer's red or black, but am I wrong here?

Image
Best, | moi
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moi
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Re: How do I replace a light switch to a dimmable switch?

Post by moi »

galawdawg wrote: Sun Jan 16, 2022 4:05 am
moi wrote: Sun Jan 16, 2022 3:00 am I am planning to replace a light switch to a dimmable light switch.

--------------------------------------------------------
First Question:
I'm confused by ground wire. How come the existing switch does NOT have a ground wire connected? Is that dangerous? Most existing dimmer switches (and light switches in general) do not have a ground wire. They simply interrupt the electricity through the "hot" wire (black). Don't worry about it.

According to the installation manual of the new dimmable switch, the new switch's green wire is supposed to be connected to the ground. However, because there isn't a ground connecting to the existing switch, do I simply NOT connect a ground to the new dimmer switch's green wire? No. Connect the green wire on the new dimmer switch to the ground wires of the circuit (the bare copper wires that are twisted together and folded in the back of your electrical box. You may need to make a "pigtail" to make the connection to those ground wires.

Inside the box, I see that the two cables comining in each have a bare copper cable, which I understand is the ground. They are connected together. Am I supposed to do something with those two bare copper wires? Or leave them alone? The current switch does not connect to those two copper wires directly. The green wire on the new dimmer switch will connect to those....see above.

When I used the walk through tutorial for the dimmer installation, there is an option to click that says "I do not have a ground in my wallbox." After I click it, it says: No ground? No problem! Don't have a ground wire? The NEC syas this is fine as long as a nonmetallic, noncombustible faceplace is used with nonmetallic attachment screws. The current light switch faceplate is plastic, and the screw to screw the faceplate to the light switch is painted (which I presume provides insulation to make the screw a non-conductor). Does this mean it's okay to not have the ground wire attached to the new dimmable switch? Ignore all of this, you do have a ground in your wallbox.

And yes I did turn off the breaker in the electrical panel before I started working on the light switch. Good. Also, be sure to use a tester to ensure all of the wires in the box have no current.

Second question:
On the current switch, when the switch is screwed into the box, I noticed there is a tiny piece of thin cardboard paper between the switch and the hole on the box. In the picture below, that piece of thin cardboard paper is on the screw. What's the purpose of that paper? It simply keeps the screw from falling out of the switch. No problem if the cardboard isn't there. Just don't lose the screw(s). :happy

Third question:
Do I use a yellow connector to connect the dimmable switch wire to the black wire coming from the box? The black wires are 14 gauge solid copper wires. The dimmable switch are 18 gauge stranded wires, and they look "silver" not copper. The yellow connectors (wire nut) chart says it could connect (1-2) 14 AWG & (1) 18 AWG. I interpret that as connect one or two 14 gauge and one 18 gauge wires are permitted using the yellow connector. Is that right? However, the manual also says, wire connectors provided are suitable for copper wire only. For aluminum wire, consult an electrition. Since the wire coming from the dimmer switch looks silver, does that mean it's something other than copper? So does that mean I cannot sue the yellow connector in this circumstance? The switch wires are not aluminum, they are stranded copper with a tinned coating to keep them from fraying or untwisting. Just use the wire connectors that Lutron provided with the switch.
Answers in red above. Hope that helps.
This is super helpful galawdawg! Except my dimmer didn't work :( Please see my other post.
Best, | moi
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moi
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Re: How do I replace a light switch to a dimmable switch?

Post by moi »

McDougal wrote: Sun Jan 16, 2022 8:51 am Hmmm. Now you've got me thinking. A dimmer switch in a bathroom. Huh.
Before I go to sleep or when I wake up at night to use the bathroom, the bright light wakes me up way too much. Very unpleasant.

Now that my new dimmer switch installation doesn't work, there's too little light there. :oops:
Best, | moi
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galawdawg
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Re: How do I replace a light switch to a dimmable switch?

Post by galawdawg »

moi wrote: Mon Jan 17, 2022 2:41 am You know I thought about which of the black wire is upstream (from the power source) and which of the black wire is downstream (sends power to the light), but the installation instructions didn't seem to care which is which, as long as one is connected to the black and one is connected to the red.
Look again at the installation instructions and particularly the wiring diagram: https://webapiaw1proddat01st01.blob.cor ... Page_4.pdf
  • The black wire on your new dimmer switch must be attached to the black wire going back to your electrical panel.
  • The red wire on your new dimmer switch must be attached to the black wire going to the light fixture(s).
moi wrote: Mon Jan 17, 2022 2:49 am Okay all. I need a little more help here.

I'm pretty sure I did this correctly (see photo below)

One black from the box to one black from the dimmer switch.

One black from the box to one red from the dimmer switch.

The red/white stripe from the dimmer is not used and capped off with blue wire nut.

The green ground wire from the switch is twisted into two bare copper wires as in a pigtail (pretty sure that's what I did)

I turned the switch on and off and NOTHING happens. Even if I turn the dimmer to the brightest.

Did I get a brand new broken switch? Or did I do something wrong? Using Lutron's instruction, I'm pretty sure it doesn't matter which black wire from the box I use to connect to the dimmer's red or black, but am I wrong here?

Image
Yes, the connection of the black and red wire from the dimmer does matter. Look at my comment above concerning attachment of the black wire to the black "hot" wire that comes from your electrical panel and attachment of the red wire to the black wire that goes to your light fixture(s). If the wiring is not correct, connect them properly and see if the switch now works.

Second, have you checked to ensure that power to the switch/light fixtures was restored at the electrical panel?

Third, did you use the rocker switch to turn the lights on before using the slide control to dim the lights?

If the black/red wires on the dimmer switch are properly connected, you have restored power to the dimmer/fixtures, and you have used the rocker switch to turn the dimmer on before using the slide dimmer and it still is not working, I'd recommend you ensure each connection is tight and that the bare wires for each connection are making good contact (as opposed to the wire insulation making contact with the other wire). If you take off each wire nut carefully, you should be able to see if the bare copper of each wire is making a good connection.

See if any of those steps resolve your issue. But remember, safety first. Turn off power at the electrical panel and use a tester to ensure there is no current to the wires or in the electrical box before doing any work.
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Re: How do I replace a light switch to a dimmable switch?

Post by Sandtrap »

galawdawg wrote: Mon Jan 17, 2022 4:29 am
moi wrote: Mon Jan 17, 2022 2:41 am You know I thought about which of the black wire is upstream (from the power source) and which of the black wire is downstream (sends power to the light), but the installation instructions didn't seem to care which is which, as long as one is connected to the black and one is connected to the red.
Look again at the installation instructions and particularly the wiring diagram: https://webapiaw1proddat01st01.blob.cor ... Page_4.pdf
  • The black wire on your new dimmer switch must be attached to the black wire going back to your electrical panel.
  • The red wire on your new dimmer switch must be attached to the black wire going to the light fixture(s).
moi wrote: Mon Jan 17, 2022 2:49 am Okay all. I need a little more help here.

I'm pretty sure I did this correctly (see photo below)

One black from the box to one black from the dimmer switch.

One black from the box to one red from the dimmer switch.

The red/white stripe from the dimmer is not used and capped off with blue wire nut.

The green ground wire from the switch is twisted into two bare copper wires as in a pigtail (pretty sure that's what I did)

I turned the switch on and off and NOTHING happens. Even if I turn the dimmer to the brightest.

Did I get a brand new broken switch? Or did I do something wrong? Using Lutron's instruction, I'm pretty sure it doesn't matter which black wire from the box I use to connect to the dimmer's red or black, but am I wrong here?

Image
Yes, the connection of the black and red wire from the dimmer does matter. Look at my comment above concerning attachment of the black wire to the black "hot" wire that comes from your electrical panel and attachment of the red wire to the black wire that goes to your light fixture(s). If the wiring is not correct, connect them properly and see if the switch now works.

Second, have you checked to ensure that power to the switch/light fixtures was restored at the electrical panel?

Third, did you use the rocker switch to turn the lights on before using the slide control to dim the lights?

If the black/red wires on the dimmer switch are properly connected, you have restored power to the dimmer/fixtures, and you have used the rocker switch to turn the dimmer on before using the slide dimmer and it still is not working, I'd recommend you ensure each connection is tight and that the bare wires for each connection are making good contact (as opposed to the wire insulation making contact with the other wire). If you take off each wire nut carefully, you should be able to see if the bare copper of each wire is making a good connection.

See if any of those steps resolve your issue. But remember, safety first. Turn off power at the electrical panel and use a tester to ensure there is no current to the wires or in the electrical box before doing any work.
Outstanding!
Great step by step points!
Well said.

*Thus my comment earlier about differentiating between which black is the "load" and which black is the "hot/feed".

Good job!
Thanks!!!
j :D
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Re: How do I replace a light switch to a dimmable switch?

Post by Sandtrap »

suemarkp wrote: Sun Jan 16, 2022 3:57 pm You can have a white wire when there are only two wires in the box (a switch loop), but you don't have that here fortunately. But Sandtrap did mention one thing that may be important. You need to know which black wire is the power source and which black wire goes to the light. The black power source wire goes to the black on the dimmer switch. The black that goes to the light goes to the red on the dimmer switch. Get them backwards and hopefully it just doesn't work. Worst case, you fry the dimmer.

You need a meter or a non contact voltage tester to determine this. With the black wires disconnected from the switch, hanging out of the box, and the live ends capped off, turn on the circuit breaker and bring the non contact tester near each black wire. The power source wire should set it off. The one going to the light should not. Remember which of the two was the power source wire, turn off the breaker, test it again with the non contact tester to make sure it is dead now, and then connect it to the black wire of the dimmer. Then connect the other wires on the dimmer.

By the way, if your house was built before 1993, or before the 1993 national electric code was in effect, switches were not required to be grounded unless they had metal faceplates (metal screws with plastic plates were OK then on ungrounded switches inside).
Perfect!

Thanks!
j :D
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Re: How do I replace a light switch to a dimmable switch?

Post by jabberwockOG »

Be aware that switch circuits can be wired two ways - 1) with the power coming into the switch box, 2) with the power coming into the light fixture (switch loop type).

Unless a dimmer is specifically marked with LINE and LOAD or similar, it doesn't matter which wire goes to which screw/pigtail in a simple two wire switch or dimmer. If the dimmer can be used as a three way, the instructions should say which screw/pigtail should not be used.

In the case of some 4 wire dimmers -
- Black is the common terminal, and is attached to the ungrounded (hot) conductor feeding the switch.
- Red is the switched lead (or a traveler in a 3-way installation), and is attached to the switched hot going to the light.
- Red with white is a traveler, used for 3-way installations. In your situation, you'll just cap this one off.
- Green is ground, and is attached to the grounding conductor.


You need a $15-25 electrical power tester light - 1) to test for power off when you trip the breaker for safety, and 2) to test which wire feed(s) are hot with power on. Something like this -

https://www.amazon.com/Southwire-Tools- ... C80&sr=8-2


Lots of utubes out there that show how to correctly replace switches. We moved into a new house in 2021. I have installed 16 dimmers in it to date.
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Re: How do I replace a light switch to a dimmable switch?

Post by michaelingp »

While I would definitely recommend switching the red and black wires from the dimmer with the two black wires in the box and see if it works, in defense of the OP, the instructions (and the video) strongly imply that for that dimmer it doesn't matter.
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Re: How do I replace a light switch to a dimmable switch?

Post by quantAndHold »

Maybe you just need one of these.
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Re: How do I replace a light switch to a dimmable switch?

Post by jharkin »

moi wrote: Mon Jan 17, 2022 2:49 am Okay all. I need a little more help here.

I'm pretty sure I did this correctly (see photo below)

One black from the box to one black from the dimmer switch.

One black from the box to one red from the dimmer switch.

The red/white stripe from the dimmer is not used and capped off with blue wire nut.

The green ground wire from the switch is twisted into two bare copper wires as in a pigtail (pretty sure that's what I did)

I turned the switch on and off and NOTHING happens. Even if I turn the dimmer to the brightest.

Did I get a brand new broken switch? Or did I do something wrong? Using Lutron's instruction, I'm pretty sure it doesn't matter which black wire from the box I use to connect to the dimmer's red or black, but am I wrong here?

Image

Read your instructions again... LED compatible Dimmers almost always need the neutral connected in addition to the incoming (from the circuit) and outgoing (to the light fixture) hot leg. There is an electronic circuit inside the dimmer which controls the dim function and that itself draws a small amount of power, which requires both a hot and neutral.

That striped wire may be the one they want you to pigtail into the neutrals but you must read the instructions carefully to be sure.
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Re: How do I replace a light switch to a dimmable switch?

Post by galawdawg »

jharkin wrote: Mon Jan 17, 2022 11:07 am Read your instructions again... LED compatible Dimmers almost always need the neutral connected in addition to the incoming (from the circuit) and outgoing (to the light fixture) hot leg.
Not the switch that OP says he purchased:
https://images.thdstatic.com/catalog/pd ... 6ced89.pdf
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Re: How do I replace a light switch to a dimmable switch?

Post by quantAndHold »

galawdawg wrote: Mon Jan 17, 2022 1:38 pm
jharkin wrote: Mon Jan 17, 2022 11:07 am Read your instructions again... LED compatible Dimmers almost always need the neutral connected in addition to the incoming (from the circuit) and outgoing (to the light fixture) hot leg.
Not the switch that OP says he purchased:
https://images.thdstatic.com/catalog/pd ... 6ced89.pdf
From that page…
If using LED or CFL bulbs, they must be Lutron compatible for optimal performance!

For the compatible bulb list, please visit www.lutron.com/dimcflled
Is the light bulb compatible?
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Re: How do I replace a light switch to a dimmable switch?

Post by inbox788 »

Sandtrap wrote: Sun Jan 16, 2022 8:23 am RE: Differentiating which "black" is the load and which "black" is the "hot/feed" is important.

j :D
I'm with you on this one.

50-50-90 rule: Anytime you have a 50-50 chance of getting something right,there's a 90% probability you'll get it wrong.

galawdawg wrote: Mon Jan 17, 2022 1:38 pm
jharkin wrote: Mon Jan 17, 2022 11:07 am Read your instructions again... LED compatible Dimmers almost always need the neutral connected in addition to the incoming (from the circuit) and outgoing (to the light fixture) hot leg.
Not the switch that OP says he purchased:
https://images.thdstatic.com/catalog/pd ... 6ced89.pdf
That appears correct and same as the link on homedepot item. Here's another insert that first comes up when you google the part number. It has the wiring diagram that's not on the one linked above.

https://ledt8bulb.com/pdf/lutron-dvcl-1 ... -guide.pdf
Last edited by inbox788 on Mon Jan 17, 2022 2:16 pm, edited 1 time in total.
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Re: How do I replace a light switch to a dimmable switch?

Post by michaelingp »

quantAndHold wrote: Mon Jan 17, 2022 1:45 pm
Is the light bulb compatible?
I've installed scores of LED lights and dimmers. In my experience, the lists are no longer useful. Modern bulbs and dimmers virtually always work together. Even in the old days, the only problem would be that when dimming the lights would flicker. Even if the LED is not "dimmable" it will work at full power.
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Re: How do I replace a light switch to a dimmable switch?

Post by moi »

galawdawg wrote: Mon Jan 17, 2022 4:29 am
Yes, the connection of the black and red wire from the dimmer does matter. Look at my comment above concerning attachment of the black wire to the black "hot" wire that comes from your electrical panel and attachment of the red wire to the black wire that goes to your light fixture(s). If the wiring is not correct, connect them properly and see if the switch now works.

Second, have you checked to ensure that power to the switch/light fixtures was restored at the electrical panel?

Third, did you use the rocker switch to turn the lights on before using the slide control to dim the lights?

If the black/red wires on the dimmer switch are properly connected, you have restored power to the dimmer/fixtures, and you have used the rocker switch to turn the dimmer on before using the slide dimmer and it still is not working, I'd recommend you ensure each connection is tight and that the bare wires for each connection are making good contact (as opposed to the wire insulation making contact with the other wire). If you take off each wire nut carefully, you should be able to see if the bare copper of each wire is making a good connection.

See if any of those steps resolve your issue. But remember, safety first. Turn off power at the electrical panel and use a tester to ensure there is no current to the wires or in the electrical box before doing any work.
Okay when I looked at the wiring diagram, then yes it DOES matter. The first time I looked at the wiring diagram I didn't understand what "line" meant. Looking at the Spanish part, it says "vivo." I take that to mean "live" wire so that made a lot more sense to me. I didn't realize "line" means the cable carrying power from the panel.

I have to say though if you go through the step by step guide or even the video, nowhere did they mention that is has to be the "hot" wire that connects to the black wire of the switch. Seems to be a bit of omission for me.

But this is super helpful. Thanks
Best, | moi
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Re: How do I replace a light switch to a dimmable switch?

Post by moi »

michaelingp wrote: Mon Jan 17, 2022 8:06 am While I would definitely recommend switching the red and black wires from the dimmer with the two black wires in the box and see if it works, in defense of the OP, the instructions (and the video) strongly imply that for that dimmer it doesn't matter.
That's what I thought! Not a single comment on the included paper instruction in the box, or the online step by step guide, or the video!
Best, | moi
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Re: How do I replace a light switch to a dimmable switch?

Post by moi »

jabberwockOG wrote: Mon Jan 17, 2022 7:40 am Be aware that switch circuits can be wired two ways - 1) with the power coming into the switch box, 2) with the power coming into the light fixture (switch loop type).

Unless a dimmer is specifically marked with LINE and LOAD or similar, it doesn't matter which wire goes to which screw/pigtail in a simple two wire switch or dimmer. If the dimmer can be used as a three way, the instructions should say which screw/pigtail should not be used.

In the case of some 4 wire dimmers -
- Black is the common terminal, and is attached to the ungrounded (hot) conductor feeding the switch.
- Red is the switched lead (or a traveler in a 3-way installation), and is attached to the switched hot going to the light.
- Red with white is a traveler, used for 3-way installations. In your situation, you'll just cap this one off.
- Green is ground, and is attached to the grounding conductor.


You need a $15-25 electrical power tester light - 1) to test for power off when you trip the breaker for safety, and 2) to test which wire feed(s) are hot with power on. Something like this -

https://www.amazon.com/Southwire-Tools- ... C80&sr=8-2


Lots of utubes out there that show how to correctly replace switches. We moved into a new house in 2021. I have installed 16 dimmers in it to date.
Yeah I was being cheap and didn't get a power tester tool. I got one finally, especially now that I know it's the hot wire that needs to connect to the black on the switch.
Best, | moi
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Re: How do I replace a light switch to a dimmable switch?

Post by moi »

quantAndHold wrote: Mon Jan 17, 2022 9:30 am Maybe you just need one of these.
Haha that wouldn't pass fit with the décor and wife probably wouldn't allow it.
Best, | moi
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Re: How do I replace a light switch to a dimmable switch?

Post by moi »

inbox788 wrote: Mon Jan 17, 2022 2:06 pm
I'm with you on this one.

50-50-90 rule: Anytime you have a 50-50 chance of getting something right,there's a 90% probability you'll get it wrong.
So this is how the story ended. I finally went to the store to pickup a voltage testing tool. And then I was thinking, what if I happened to get the connection right (hot wire to black wire)? What if the switch WAS the problem? So I bought an extra switch just in case.

Also, the first switch I got... it looks used. When I opened the box initially, the plastic packaging for the included wire nuts was open already, and the nuts look dirty, as if they were used. But at that time I was too lazy to go back to the store and I was thinking what are the chances that Home Depot would sell a broken switch?

So when I went home, the voltage tester confirmed that I CORRECTLY wired the switch. So I was thinking, the switch must be broken. So when I replaced it with a new switch, wiring it exactly the way I showed on the photo (striped red not used). IT WORKED!!! Man what kind of luck do I have to get a broken switch on my very first DIY electrical switch project?

Thanks everyone for all the advise. You're all incredibly helpful. And now I'm going to enjoy my soft dim light during my last bathroom break before I go sleep :D It's so nice not to get strong flash of light right before I want to sleep.

Now I'm eyeing some of these older ceiling fan switches around the house and thinking about changing them to the fancier Lutron ones..... I got a taste and now I want more!
Best, | moi
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Re: How do I replace a light switch to a dimmable switch?

Post by Cubicle »

I have dimmers on 95% of switches in my house. Like you & others have discovered, it is very underrated...

Congrats. Go forth & tinker some more.
$1 saved = >$1 earned. ✓
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Re: How do I replace a light switch to a dimmable switch?

Post by wilked »

More than anything I’m glad you purchased a NCVT. Do not touch any wire in the future before you check they are dead.

The procedure is - test a known hot wire to ensure NCVT is working
Then test your wires you are to work on to verify dead
Then re-rest a known hot wire to verify NCVT still working

Learn good habits and you’ll keep yourself safe.

Nice work on the project by the way!

Last note while I’m thinking on it - if your electric box was metal that box would have also had to have been grounded. Just an FYI
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Re: How do I replace a light switch to a dimmable switch?

Post by Sandtrap »

moi wrote: Fri Jan 21, 2022 2:59 am
inbox788 wrote: Mon Jan 17, 2022 2:06 pm
I'm with you on this one.

50-50-90 rule: Anytime you have a 50-50 chance of getting something right,there's a 90% probability you'll get it wrong.
So this is how the story ended. I finally went to the store to pickup a voltage testing tool. And then I was thinking, what if I happened to get the connection right (hot wire to black wire)? What if the switch WAS the problem? So I bought an extra switch just in case.

Also, the first switch I got... it looks used. When I opened the box initially, the plastic packaging for the included wire nuts was open already, and the nuts look dirty, as if they were used. But at that time I was too lazy to go back to the store and I was thinking what are the chances that Home Depot would sell a broken switch?

So when I went home, the voltage tester confirmed that I CORRECTLY wired the switch. So I was thinking, the switch must be broken. So when I replaced it with a new switch, wiring it exactly the way I showed on the photo (striped red not used). IT WORKED!!! Man what kind of luck do I have to get a broken switch on my very first DIY electrical switch project?

Thanks everyone for all the advise. You're all incredibly helpful. And now I'm going to enjoy my soft dim light during my last bathroom break before I go sleep :D It's so nice not to get strong flash of light right before I want to sleep.

Now I'm eyeing some of these older ceiling fan switches around the house and thinking about changing them to the fancier Lutron ones..... I got a taste and now I want more!
:sharebeer
Glad it worked out well for you.

Lesson: There is indeed a difference between 2 black wires for a light switch and a protocol for doing things safetly.

Now, about that ceiling fan switch. . . . on your next post. . . don't forget pictures. . .

Hurray!

**Huge help from "galawdawg". Thanks!

j :D
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Re: How do I replace a light switch to a dimmable switch?

Post by michaelingp »

moi wrote: Fri Jan 21, 2022 2:59 am
Also, the first switch I got... it looks used. When I opened the box initially, the plastic packaging for the included wire nuts was open already, and the nuts look dirty, as if they were used. But at that time I was too lazy to go back to the store and I was thinking what are the chances that Home Depot would sell a broken switch?
I've gotten burned at Home Depot several times (Amazon Warehouse too). Now I try to inspect everything I buy. You know those little bags with screws and nuts in them? You have to count them before you buy!
So when I went home, the voltage tester confirmed that I CORRECTLY wired the switch. So I was thinking, the switch must be broken. So when I replaced it with a new switch, wiring it exactly the way I showed on the photo (striped red not used). IT WORKED!!! Man what kind of luck do I have to get a broken switch on my very first DIY electrical switch project?
Well, you should have done the science and reported back and ended the BH controversy. Now that you know you have a working switch, re-wire it with the black wires reversed, and tell us if it still works. I'm betting that it will still work. Lutron is pretty good about making sure the instructions are correct, and switch makers are always improving the electronics to improve customer experience. (By the way, I'm just kidding! Enjoy the light. Someone else can figure out if it matters which wire goes to which!)
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Re: How do I replace a light switch to a dimmable switch?

Post by quantAndHold »

moi wrote: Fri Jan 21, 2022 2:46 am
quantAndHold wrote: Mon Jan 17, 2022 9:30 am Maybe you just need one of these.
Haha that wouldn't pass fit with the décor and wife probably wouldn't allow it.
We got one of these as a gag gift several years ago. It turned out to be super useful. Go figure.

Glad you figured it out.
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