# flickering fluorescent lights

**URL:** <https://boards.straightdope.com/t/flickering-fluorescent-lights/400128>\
**Category:** Factual Questions\
**Created:** [April 14, 2007, 6:01pm UTC](https://boards.straightdope.com/t/flickering-fluorescent-lights/400128 "2007-04-14T18:01:26Z")\
**Posts on this page:** 5\
**Page:** 1

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**Author:** ![solkoe](https://avatars.discourse-cdn.com/v4/letter/s/919ad9/32.png) [@solkoe](https://boards.straightdope.com/u/solkoe)\
**Post date:** [April 14, 2007, 6:01pm UTC](https://boards.straightdope.com/t/flickering-fluorescent-lights/400128/1 "2007-04-14T18:01:26Z")

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I have some old fluorescent receptacles that I am trying to install. One doesn’t work at all and two other give a dim flickering light. Is it the ballast that needs to be replaced or is it the bulb?

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**Author:** ![Harmonious\_Discord](https://avatars.discourse-cdn.com/v4/letter/h/74df32/32.png) [@Harmonious\_Discord](https://boards.straightdope.com/u/Harmonious_Discord)\
**Post date:** [April 14, 2007, 6:15pm UTC](https://boards.straightdope.com/t/flickering-fluorescent-lights/400128/2 "2007-04-14T18:15:12Z")

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On old flouresent fixtures they had a starter, which is what normaly needed replacing. It’s a small metal cylinder about 1 inch diameter by one and a half inches in length. The next thing to try is the light bulb. The ballast is the last thing likely to go with a flickering light.

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**Author:** ![Will\_Repair](https://avatars.discourse-cdn.com/v4/letter/w/a698b9/32.png) [@Will\_Repair](https://boards.straightdope.com/u/Will_Repair)\
**Post date:** [April 14, 2007, 7:25pm UTC](https://boards.straightdope.com/t/flickering-fluorescent-lights/400128/3 "2007-04-14T19:25:52Z")

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First replace the lamps (and starter if there is one.) Then if still a no-go then replace the ballast.  
This is based on time and parts costs.

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**Author:** ![solkoe](https://avatars.discourse-cdn.com/v4/letter/s/919ad9/32.png) [@solkoe](https://boards.straightdope.com/u/solkoe)\
**Post date:** [April 14, 2007, 9:59pm UTC](https://boards.straightdope.com/t/flickering-fluorescent-lights/400128/4 "2007-04-14T21:59:11Z")

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[QUOTE=Harmonious Discord]  
On old flouresent fixtures they had a starter, which is what normaly needed replacing. It’s a small metal cylinder about 1 inch diameter by one and a half inches in length. The next thing to try is the light bulb. The ballast is the last thing likely to go with a flickering light.  
[/QUOTE]

I cannot find the starter. It ballast and lot of wiring. Is it possible that the fixture is not that old? I notice that one of the lamps has black at one of its ends. Is that a sign that it is bad?  
BTW - How does a lamp wear out? There is no filament. It’s just a fluorescent gas.

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**Author:** ![jayjay](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/jayjay/32/6765_2.png) [@jayjay](https://boards.straightdope.com/u/jayjay)\
**Post date:** [April 15, 2007, 4:53am UTC](https://boards.straightdope.com/t/flickering-fluorescent-lights/400128/5 "2007-04-15T04:53:19Z")

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[QUOTE=solkoe]  
BTW - How does a lamp wear out? There is no filament. It’s just a fluorescent gas.  
[/QUOTE]

The electrodes can fail through age. The phosphor layer has a half-life, and gradually grows dimmer as it ages. The mercury vapor can become absorbed by the phosphor, the glass and the electrodes and eventually fall below operating levels.

[Wiki article on fluorescent lamps](http://en.wikipedia.org/wiki/Fluorescent_lamp)…the causes of operational failure are about 1/3 of the way down the page.