# How do I fix my dimmer switch? **URL:** \ **Category:** Factual Questions\ **Created:** [July 2, 2003, 6:57pm UTC](https://boards.straightdope.com/t/how-do-i-fix-my-dimmer-switch/185833 "2003-07-02T18:57:27Z")\ **Posts on this page:** 15\ **Page:** 1
**Author:** ![Sunshine](https://avatars.discourse-cdn.com/v4/letter/s/3ec8ea/32.png) [@Sunshine](https://boards.straightdope.com/u/Sunshine)\ **Post date:** [July 2, 2003, 6:57pm UTC](https://boards.straightdope.com/t/how-do-i-fix-my-dimmer-switch/185833/1 "2003-07-02T18:57:27Z")
We have a dimmer switch in our dining room, which I love! But the other day, I turned on the light in there to “full blast” and it made a popping sound and the light went out. I figured the bulb just burnt out but then discovered that the fuse had blown when I tried to turn on another light. So I went and re-set the switch in the fuse box and the dimmer light still didn’t work, so we put in a new bulb. Now the dimmer part doesn’t work–it’s just on or off! I thought maybe you need a special lightbulb so I looked at the store but the only thing I saw was a three way bulb, so I got that and put it in but still no dimming. Am I missing something here? Do you need a special bulb? Or is there something else that is wrong? Any ideas on how to fix my dimmer would be greatly appreciated! ---
**Author:** ![GaryM](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/garym/32/241_2.png) [@GaryM](https://boards.straightdope.com/u/GaryM)\ **Post date:** [July 2, 2003, 7:00pm UTC](https://boards.straightdope.com/t/how-do-i-fix-my-dimmer-switch/185833/2 "2003-07-02T19:00:51Z")
“No consumer replaceable parts inside” Well it doesn’t say that but unless you just want some exercise don’t bother. The Triac is probably shorted, and these are not made to have parts replaced. Spend the $10 and buy a new one. ---
**Author:** ![ElvisL1ves](https://avatars.discourse-cdn.com/v4/letter/e/5daacb/32.png) [@ElvisL1ves](https://boards.straightdope.com/u/ElvisL1ves)\ **Post date:** [July 2, 2003, 7:01pm UTC](https://boards.straightdope.com/t/how-do-i-fix-my-dimmer-switch/185833/3 "2003-07-02T19:01:38Z")
You don’t need a special bulb as long as it’s incandescent (fluorescents can’t be dimmed). The dimmer switch itself may be shot. The can’t be fixed, only replaced, but they don’t cost that much, around US$10 or less. Just remember to shut off the breaker to that circuit before replacing the switch. ---
**Author:** ![Q.E.D](https://avatars.discourse-cdn.com/v4/letter/q/51bf81/32.png) [@Q.E.D](https://boards.straightdope.com/u/Q.E.D)\ **Post date:** [July 2, 2003, 7:07pm UTC](https://boards.straightdope.com/t/how-do-i-fix-my-dimmer-switch/185833/4 "2003-07-02T19:07:38Z")
> [@](#): > > \*Originally posted by ElvisL1ves \* > **…fluorescents can’t be dimmed…** Not quite true. You _do_ need a special dimming ballast, though. A standard dimmer will not work: > [@](#): > > A dimming ballast must be installed to dim fluorescent lamps. A fluorescent lamp dimmer works in tandem with the dimming ballast to lower the light level. The wiring diagrams provided by manufacturers are important because fluorescent lamp dimmers require more wiring than incandescent lamp dimmers. From [here.](http://www.lrc.rpi.edu/programs/lightingTransformation/residentialLighting/buildersGuide/controls.asp) ---
**Author:** ![UnwrittenNocturne](https://avatars.discourse-cdn.com/v4/letter/u/6de8d8/32.png) [@UnwrittenNocturne](https://boards.straightdope.com/u/UnwrittenNocturne)\ **Post date:** [July 2, 2003, 7:12pm UTC](https://boards.straightdope.com/t/how-do-i-fix-my-dimmer-switch/185833/5 "2003-07-02T19:12:48Z")
Don’t they use a simple potentiometer? if so that ought not be too tough to fix…will take one apart and check later ---
**Author:** ![Q.E.D](https://avatars.discourse-cdn.com/v4/letter/q/51bf81/32.png) [@Q.E.D](https://boards.straightdope.com/u/Q.E.D)\ **Post date:** [July 2, 2003, 7:29pm UTC](https://boards.straightdope.com/t/how-do-i-fix-my-dimmer-switch/185833/6 "2003-07-02T19:29:43Z")
> [@](#): > > \*Originally posted by UnwrittenNocturne \* > \*\*Don’t they use a simple potentiometer? if so that ought not be too tough to fix…will take one apart and check later \*\* Older dimmers did just that. The new ones are usually electronic, employing an SCR called a triac. The circuitry controls where in the AC cycle the triac is turned on, and thereby the total power delivered to the bulb. ---
**Author:** ![Sunshine](https://avatars.discourse-cdn.com/v4/letter/s/3ec8ea/32.png) [@Sunshine](https://boards.straightdope.com/u/Sunshine)\ **Post date:** [July 2, 2003, 7:47pm UTC](https://boards.straightdope.com/t/how-do-i-fix-my-dimmer-switch/185833/7 "2003-07-02T19:47:57Z")
Ok, you guys have used a bunch of words I don’t understand in relation to light switches, _(Triac? ballast? potentionomosaxophonometer?!)_ so what I’m getting from this is I should just truck my butt down to Home Depot and get a new one for around 10 bucks. That should work. But, to quote Hubby, “I am not an electrician.” which means I’ll prolly end up doing this myself. How hard will it be? Please note that I am an instruction fanatic and will definitely read all instructions that come with the thing but would like some idea of what I’m getting in to. Hubby and I _were_ able to tag-team replace our garbage disposal with no apparent trouble, so how does this compare (aside from the obvious bonus of not weighing 80 million pounds)? Oh, and uh, any special tools that don’t come in the standard _Do It Herself_ took kit that I’ll need to pick up whilst at Home Depot? Muchas Gracias for the help! ---
**Author:** ![GaryM](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/garym/32/241_2.png) [@GaryM](https://boards.straightdope.com/u/GaryM)\ **Post date:** [July 2, 2003, 7:47pm UTC](https://boards.straightdope.com/t/how-do-i-fix-my-dimmer-switch/185833/8 "2003-07-02T19:47:57Z")
As **Q.E.D.** said, they don’t do that anymore. A variable resistor to handle 150 watts is not a small item either. See here for a ful explaination [http://home.howstuffworks.com/dimmer-switch.htm](http://home.howstuffworks.com/dimmer-switch.htm) ---
**Author:** ![Q.E.D](https://avatars.discourse-cdn.com/v4/letter/q/51bf81/32.png) [@Q.E.D](https://boards.straightdope.com/u/Q.E.D)\ **Post date:** [July 2, 2003, 7:51pm UTC](https://boards.straightdope.com/t/how-do-i-fix-my-dimmer-switch/185833/9 "2003-07-02T19:51:10Z")
Installation is fairly straightforward, \*\* Sunshine\*\*. You’ll wire it exactly the same way the one in there now is. Just remember to SHUT OFF THE CIRCUIT BREAKER FIRST. ---
**Author:** ![lieu](https://avatars.discourse-cdn.com/v4/letter/l/c2a13f/32.png) [@lieu](https://boards.straightdope.com/u/lieu)\ **Post date:** [July 2, 2003, 7:52pm UTC](https://boards.straightdope.com/t/how-do-i-fix-my-dimmer-switch/185833/10 "2003-07-02T19:52:27Z")
Please make sure you’ve got the correct circuit breaker flipped! ---
**Author:** ![Q.E.D](https://avatars.discourse-cdn.com/v4/letter/q/51bf81/32.png) [@Q.E.D](https://boards.straightdope.com/u/Q.E.D)\ **Post date:** [July 2, 2003, 7:57pm UTC](https://boards.straightdope.com/t/how-do-i-fix-my-dimmer-switch/185833/11 "2003-07-02T19:57:50Z")
Yes, while you’re at Home Depot, pick up a non-contact voltage sensor. This will tell you if the circuit is energized or not. Other than that, you’ll need no special tools. A standard slotted screwdriver, wirecutters and possibly wire strippers is all you’ll need. ---
**Author:** ![Philster](https://avatars.discourse-cdn.com/v4/letter/p/13edae/32.png) [@Philster](https://boards.straightdope.com/u/Philster)\ **Post date:** [July 2, 2003, 7:58pm UTC](https://boards.straightdope.com/t/how-do-i-fix-my-dimmer-switch/185833/12 "2003-07-02T19:58:01Z")
I did this twice now in my lifetime (blow a dimmer switch), and I can tell you it tastes funny. Seriously, I just did it again - kill a dimmer switch - when I crossed some wires. Dimmer part is busted, but the light works. Don’t play with electricity - buy a new switch. One question…Does another switch also work the light you are dimming? If so, the dimmer switch will need to be a 3-way dimmer -yes 3-way dimmer- and will be a few bucks closer to 20 bucks. ---
**Author:** ![justwannano](https://avatars.discourse-cdn.com/v4/letter/j/7ab992/32.png) [@justwannano](https://boards.straightdope.com/u/justwannano)\ **Post date:** [July 2, 2003, 7:59pm UTC](https://boards.straightdope.com/t/how-do-i-fix-my-dimmer-switch/185833/13 "2003-07-02T19:59:03Z")
Make sure the total wattage of your light bulb(s) do not exceed the rate of the dimmer. Back in the olden days a friend ,another electronics tech, and I tended bar. The lights above the bar were on a dimmer switch. One week I replaced the switch 2 times. Some yokel had replaced the 40 watt light bulbs with 60’s. The lights did quite well until closing time when they were turned up to clean. It took two replacements to figure that one out. ---
**Author:** ![Sunshine](https://avatars.discourse-cdn.com/v4/letter/s/3ec8ea/32.png) [@Sunshine](https://boards.straightdope.com/u/Sunshine)\ **Post date:** [July 2, 2003, 9:09pm UTC](https://boards.straightdope.com/t/how-do-i-fix-my-dimmer-switch/185833/14 "2003-07-02T21:09:22Z")
All good tips. Thanks everyone. **Philster** , to answer your question, nope, there’s only one switch. But thanks for the mention. And **justwannano** , thanks for the mention on watts also. Never crossed my mind that there was an upper limit. Luckily the bulb we put in is only 40 watts so I know that’s not causing the problem. Can’t wait to try this! Maybe I can even go to Home Depot tonight. ---
**Author:** ![Early\_Out](https://avatars.discourse-cdn.com/v4/letter/e/6f9a4e/32.png) [@Early\_Out](https://boards.straightdope.com/u/Early_Out)\ **Post date:** [July 2, 2003, 9:17pm UTC](https://boards.straightdope.com/t/how-do-i-fix-my-dimmer-switch/185833/15 "2003-07-02T21:17:33Z")
> [@](#): > > \*Originally posted by Sunshine \* > \*\*Hubby and I _were_ able to tag-team replace our garbage disposal with no apparent trouble, so how does this compare (aside from the obvious bonus of not weighing 80 million pounds)? \*\* This will be _ **WAY** _ easier, unless that dimmer switch is also located underneath a sink, where you have to work on your back, or on your hands and knees, and where you can’t see what you’re doing! Shouldn’t take more than about two minutes.