Why do my bathroom lights need to be smacked to turn on?

Old 06-05-20, 07:13 PM
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Why do my bathroom lights need to be smacked to turn on?

Stubborn bathroom lights https://imgur.com/a/WJ9sME1

These are new bulbs. Takes a few minutes or never to turn on otherwise half the time if I knock them a little they'll turn on. I've wiggled them in their sockets to make sure they're in place. What's usually the issue here?
Old 06-05-20, 07:15 PM
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Well judging by the black ends, the bulbs are pretty clearly quite old. There could be a starter in there that is old and worn out. They look like a small aluminum cylinder. You just give it a turn and pull it out. They still sell replacement starters.
Old 06-05-20, 07:48 PM
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I can't make out the size from the picture (are they 4' or 2' lamps/tubes) if either they could be the wrong tubes for the fixture ( for 4' lamps they will be F40T12 or F32T8 same with the 2' that are F20T12 & F17T8) they will fit in the same fixtures however they may not work reliably or at all and if they light you will get severely shortened lamp life.

Also if this a rapid start system I would check to see if the ground is properly connected for proper lamp starting & safety.
Old 06-05-20, 10:22 PM
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Newer tubes have less mercury in them and do not work well with older magnetic ballasts.
You can upgrade to an electronic ballast or consider replacing the tubes or the entire fixture with an LED equivalent.

When you smack the tubes you are jarring the pins in the socket causing a momentary disconnect.
Old 06-06-20, 01:44 AM
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or consider replacing the tubes or the entire fixture with an LED equivalent.
Dont ever repair old fluorescent lights, get them converted to LED, fluorescent lighting is such old technology!
Norm201 voted this post useful.
Old 06-06-20, 04:19 AM
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I agree with Xsleeper's assessment, but I think Marq's solution is the best.
Old 06-06-20, 04:21 AM
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I would replace them with LED's.

Rewire the fixture to get rid of the ballast.
Also I would get dimmable LED's as they may be too bright for you and if they are then you can install a dimmer to control the light output.
Also I recommend the type that get power from each end instead of the type that have Neutral and Line wired into one end (tombstone)

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