# Compact Fluorescent Light Bulb Questions? **URL:** \ **Category:** Factual Questions\ **Created:** [February 8, 2007, 9:34pm UTC](https://boards.straightdope.com/t/compact-fluorescent-light-bulb-questions/391417 "2007-02-08T21:34:49Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![AskNott](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/asknott/32/5790_2.png) [@AskNott](https://boards.straightdope.com/u/AskNott)\ **Post date:** [February 8, 2007, 9:34pm UTC](https://boards.straightdope.com/t/compact-fluorescent-light-bulb-questions/391417/1 "2007-02-08T21:34:49Z")
There’s a lot of hoopla about CFLBs lately, and I have my doubts. I read through this thread [http://boards.straightdope.com/sdmb/showthread.php?t=401857&highlight=compact+fluorescent](http://boards.straightdope.com/sdmb/showthread.php?t=401857&highlight=compact+fluorescent) from last year and didn’t find the answers I wanted. If they are used outdoors, will they dim in cold weather, as the straight tubes do? Does it matter if I use them base-down, base-up, or sideways? Are they vulnerable to vibration failure? As I write this, NPR’s _All Things Considered \* is doing a feature on the CFLB, and Wal_Mart’s big push to sell them. I know it’s terribly tempting, but could we belay the light bulb jokes until we get some serious answers? I haven’t even posted the thread yet, and I can hear them bouncing against the windows like June bugs. 😉 ---
**Author:** ![AskNott](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/asknott/32/5790_2.png) [@AskNott](https://boards.straightdope.com/u/AskNott)\ **Post date:** [February 8, 2007, 9:40pm UTC](https://boards.straightdope.com/t/compact-fluorescent-light-bulb-questions/391417/2 "2007-02-08T21:40:25Z")
Here’s a link to the NPR story. [Do Fluorescent Bulbs Light the Way to the Future? : NPR](http://www.npr.org/templates/story/story.php?storyId=7279952) ---
**Author:** ![Joey\_P](https://avatars.discourse-cdn.com/v4/letter/j/919ad9/32.png) [@Joey\_P](https://boards.straightdope.com/u/Joey_P)\ **Post date:** [February 8, 2007, 9:50pm UTC](https://boards.straightdope.com/t/compact-fluorescent-light-bulb-questions/391417/3 "2007-02-08T21:50:06Z")
IME I had one that worked and lots that died within a day of putting them outside. It should be noted though that they are/were all on 24/7, but the weather was sub-freezing. For the time being, I’m sticking with regular bulbs for outdoor use. ---
**Author:** ![TimeWinder](https://avatars.discourse-cdn.com/v4/letter/t/bcef8e/32.png) [@TimeWinder](https://boards.straightdope.com/u/TimeWinder)\ **Post date:** [February 8, 2007, 9:58pm UTC](https://boards.straightdope.com/t/compact-fluorescent-light-bulb-questions/391417/4 "2007-02-08T21:58:25Z")
I use a lot of them, but I’ve had three bad experiences. - I had a garage door opener and was using a CF bulb in it. It (and it’s replacement) burned out almost immediately – I’m guessing vibration. - In a different house, I used two CF bulbs in separate fixtures in the garage – they wouldn’t “come on” right - they’d flicker off and on several times a second. Replacing EITHER of them with an incad solved the problem. - I had one CF bulb melt, and emit smoke and maybe fire (I turned it off awfully quick). This was in a partially-enclosed fixture in the dining room; I’ve stopped putting CF’s there, as well. On the other hand, the half-dozen or so other ones I’ve used have lasted years. ---
**Author:** ![Cheesesteak](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/cheesesteak/32/3694_2.png) [@Cheesesteak](https://boards.straightdope.com/u/Cheesesteak)\ **Post date:** [February 8, 2007, 10:00pm UTC](https://boards.straightdope.com/t/compact-fluorescent-light-bulb-questions/391417/5 "2007-02-08T22:00:15Z")
My parents had compact fluorescents outside, and in the winter they were just this side of useless for about 5 minutes until they warmed up. These were somewhat older technology bulbs, so I can’t say whether or not this issue has been defeated, but it was a bear back then. I’m not aware of any orientation issues, but be cautious about having them in enclosed fixtures, I know some are not suited for that use. ---
**Author:** ![Hampshire](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/hampshire/32/4887_2.png) [@Hampshire](https://boards.straightdope.com/u/Hampshire)\ **Post date:** [February 8, 2007, 10:04pm UTC](https://boards.straightdope.com/t/compact-fluorescent-light-bulb-questions/391417/6 "2007-02-08T22:04:02Z")
I have 3 currently being used outdoors in inverted fixtures. These however were noted on the packaging as “outdoor” use and have an additional plastic bulb encasing the tisty tube part and were a bit more expensive. For the record it has been on average -10 degrees outside for the past 5 days. If turned on cold it takes them quite a while to get up to full brightness when it’s freezing outside but they do get there. The only problem with them is I have yet to find them short enough lenghtwise for certain fixtures. Even the ones advertised as “extra-short” are longer than a standard bulb. ---
**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:** [February 8, 2007, 10:05pm UTC](https://boards.straightdope.com/t/compact-fluorescent-light-bulb-questions/391417/7 "2007-02-08T22:05:00Z")
There are CFLs for outdoor use which are less susceptible to the problems that standard CFLs have outside. ---
**Author:** ![Tim\_T-Bonham.net](https://avatars.discourse-cdn.com/v4/letter/t/46a35a/32.png) [@Tim\_T-Bonham.net](https://boards.straightdope.com/u/Tim_T-Bonham.net)\ **Post date:** [February 8, 2007, 10:43pm UTC](https://boards.straightdope.com/t/compact-fluorescent-light-bulb-questions/391417/8 "2007-02-08T22:43:14Z")
I have a motion-activated fixture on the sidewalk from the garage, with 2 ‘outdoor’ CFL floodlights in it. In cold weather (like recently), they are dim when they come on (though still enough to light up the sidewalk & steps). They take 15-30 seconds to get to full brightness. But given that they use less than 1/3 of the electricity of the previous incandescent floodlamps, and are rated to last much longer (they have _already_ outlasted a typical floodlamp), I am quite satisfied with them. ---
**Author:** ![According\_to\_Pliny](https://avatars.discourse-cdn.com/v4/letter/a/8e7dd6/32.png) [@According\_to\_Pliny](https://boards.straightdope.com/u/According_to_Pliny)\ **Post date:** [February 8, 2007, 10:50pm UTC](https://boards.straightdope.com/t/compact-fluorescent-light-bulb-questions/391417/9 "2007-02-08T22:50:38Z")
The main problem I’ve had with them, and I’ve installed hundreds in various buildings, is that the larger ones (replacing 65w flood lights) tend to “warm up” by lighting only 1/3 of the coil, then a few seconds later the 2nd 1/3 and a few seconds later they are full on. This makes them useless in many applications, like storage closets, where you want to turn the light on, reach in for something, and turn it off. ---
**Author:** ![Tim\_T-Bonham.net](https://avatars.discourse-cdn.com/v4/letter/t/46a35a/32.png) [@Tim\_T-Bonham.net](https://boards.straightdope.com/u/Tim_T-Bonham.net)\ **Post date:** [February 8, 2007, 11:33pm UTC](https://boards.straightdope.com/t/compact-fluorescent-light-bulb-questions/391417/10 "2007-02-08T23:33:05Z")
[QUOTE=According to Pliny] The main problem I’ve had with them, and I’ve installed hundreds in various buildings, is that the larger ones (replacing 65w flood lights) tend to “warm up” by lighting only 1/3 of the coil, then a few seconds later the 2nd 1/3 and a few seconds later they are full on. This makes them useless in many applications, like storage closets, where you want to turn the light on, reach in for something, and turn it off. [/QUOTE] True. But such locations are bad choices for CFL bulbs – they are only burning for a short time, and you want instant-on. Those are good places to put the incandescent bulbs you removed from locations where the light is burning for hours at a time, like in a kitchen or office room. That’s where a CFL bulb will save you on electricity & replacement cost. Feel free to keep using old incandescent bulbs in places like closets – when the light’s only on for 30 seconds or so, the electricity use hardly matters. So you can save by recycling your current incandescent bulbs into those locations. ---
**Author:** ![AskNott](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/asknott/32/5790_2.png) [@AskNott](https://boards.straightdope.com/u/AskNott)\ **Post date:** [February 9, 2007, 1:24pm UTC](https://boards.straightdope.com/t/compact-fluorescent-light-bulb-questions/391417/11 "2007-02-09T13:24:53Z")
The two outdoor fixtures I’m considering are long-burning uses. One is base-up in a fixture that’s enclosed except on the bottom; it’s on all day, all night. The other is base-down in a fully enclosed but not airtight yard light; it’s on a photo switch, so it’s on from dusk to dawn. Slow starting wouldn’t be a problem, as long as they do reach full brightness in the cold. ---
**Author:** ![Bookkeeper](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bookkeeper/32/281_2.png) [@Bookkeeper](https://boards.straightdope.com/u/Bookkeeper)\ **Post date:** [February 9, 2007, 6:45pm UTC](https://boards.straightdope.com/t/compact-fluorescent-light-bulb-questions/391417/12 "2007-02-09T18:45:19Z")
I use cheap, not outdoor specific, CFBs in two outdoor fixtures - one base up and one base down. The only problems I have had with them is that they are dimmer in cold winter tempuratures (below 0 F). They are on 24/7 so slow response isn’t an issue, however. I find them to be superior to incandescents both for the cost saving in an always-on bulb and the longer life, as both fixtures inconveniently require a ladder and a screwdriver in order to replace the bulb. ---
**Author:** ![solkoe](https://avatars.discourse-cdn.com/v4/letter/s/919ad9/32.png) [@solkoe](https://boards.straightdope.com/u/solkoe)\ **Post date:** [February 9, 2007, 7:02pm UTC](https://boards.straightdope.com/t/compact-fluorescent-light-bulb-questions/391417/13 "2007-02-09T19:02:15Z")
I use two normal CFB’s outside and have had no problem with them. We live in Canada and see a wide range of temperatures. If they are dimmer in the winter, I have not noticed. By the way, that earlier thread mentioned CFB’s that work with dimmer switches. I have looked for them but had no luck. Doe anyone have further info on them? ---
**Author:** ![AskNott](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/asknott/32/5790_2.png) [@AskNott](https://boards.straightdope.com/u/AskNott)\ **Post date:** [February 9, 2007, 7:09pm UTC](https://boards.straightdope.com/t/compact-fluorescent-light-bulb-questions/391417/14 "2007-02-09T19:09:36Z")
Regular fluorescent lights can be run on a dimmer, but it takes a special kind of dimmer. I don’t know the details. ---
**Author:** ![Bosda\_Di\_Chi\_of\_Tricor](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bosda_di_chi_of_tricor/32/16845_2.png) [@Bosda\_Di\_Chi\_of\_Tricor](https://boards.straightdope.com/u/Bosda_Di_Chi_of_Tricor)\ **Post date:** [February 9, 2007, 7:18pm UTC](https://boards.straightdope.com/t/compact-fluorescent-light-bulb-questions/391417/15 "2007-02-09T19:18:19Z")
BTW–I recently located 3-way Fl. bulbs. Didn’t know they made em. ---
**Author:** ![Jake](https://avatars.discourse-cdn.com/v4/letter/j/f475e1/32.png) [@Jake](https://boards.straightdope.com/u/Jake)\ **Post date:** [February 9, 2007, 9:12pm UTC](https://boards.straightdope.com/t/compact-fluorescent-light-bulb-questions/391417/16 "2007-02-09T21:12:56Z")
A couple years ago I replaced all my incandescent bulbs with CFB’s (CFL?) and I’m glad I did. Only problem was my front porch light, which burned out after a few weeks. I don’t remember seeing any outdoor-specific bulbs at the time in the store, though. ---
**Author:** ![Uncommon\_Sense](https://avatars.discourse-cdn.com/v4/letter/u/f9ae1b/32.png) [@Uncommon\_Sense](https://boards.straightdope.com/u/Uncommon_Sense)\ **Post date:** [February 9, 2007, 9:16pm UTC](https://boards.straightdope.com/t/compact-fluorescent-light-bulb-questions/391417/17 "2007-02-09T21:16:41Z")
[QUOTE=AskNott] Regular fluorescent lights can be run on a dimmer, but it takes a special kind of dimmer. I don’t know the details. [/QUOTE] It’s the other way around. It takes a special flourescent bulb to be dimmed. ---
**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:** [February 9, 2007, 9:25pm UTC](https://boards.straightdope.com/t/compact-fluorescent-light-bulb-questions/391417/18 "2007-02-09T21:25:28Z")
[QUOTE=Uncommon Sense] It’s the other way around. It takes a special flourescent bulb to be dimmed. [/QUOTE] Not quite. In the case of standard fl **uo** rescent _tubes_, they don’t have to be anything special; it’s the _ballast_ that needs to be specifically designed to be used with a dimmer. And not just any dimmer, it has to be one also specifically designed to dim that particular ballast. And naturally, one manufacturer’s dimmers usually won’t work on another’s ballasts and vice versa. ---
**Author:** ![Stranger\_On\_A\_Train](https://avatars.discourse-cdn.com/v4/letter/s/13edae/32.png) [@Stranger\_On\_A\_Train](https://boards.straightdope.com/u/Stranger_On_A_Train)\ **Post date:** [February 9, 2007, 11:02pm UTC](https://boards.straightdope.com/t/compact-fluorescent-light-bulb-questions/391417/19 "2007-02-09T23:02:22Z")
[QUOTE=Q.E.D.] Not quite. In the case of standard fl **uo** rescent _tubes_, they don’t have to be anything special; it’s the _ballast_ that needs to be specifically designed to be used with a dimmer. And not just any dimmer, it has to be one also specifically designed to dim that particular ballast. And naturally, one manufacturer’s dimmers usually won’t work on another’s ballasts and vice versa. [/QUOTE] Great, so they’re like AC adaptors. :rolleyes: Applications that require “instant on” light are well served by [LED cluster bulbs](http://en.wikipedia.org/wiki/Solid-state_lighting), plus these are more robust (nearly indestructable, actually) than either compact fluorescent or incandescent bulbs. Stranger ---
**Author:** ![danceswithcats](https://avatars.discourse-cdn.com/v4/letter/d/9e8a1a/32.png) [@danceswithcats](https://boards.straightdope.com/u/danceswithcats)\ **Post date:** [February 10, 2007, 1:01am UTC](https://boards.straightdope.com/t/compact-fluorescent-light-bulb-questions/391417/20 "2007-02-10T01:01:31Z")
Last year, I replaced all of the exterior Edison base incandescent lamps at our fire station with CFLs. All are base up burn, rated to -30F, and are working quite well, despite single digit temperatures around here, of late. [Next page](https://boards.straightdope.com/t/compact-fluorescent-light-bulb-questions/391417.md?page=2)