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I need to replace two fluorescent lamps in my bathroom and neither of them would rotate in their sockets. I can twist them maybe 10 degrees or so but after that they completely stop moving.

It's the first time I'm changing such lamps so I'm not entirely sure how much force I should be applying but from watching videos online I feel like it should not require much force, and I got to the point where I'm applying as much torque as I can, grabbing to the metal ends of the bulb. So I'm wondering whether I'm missing some «unlock» step.

I can see in the gap between the bulb and the socket that the pins are currently vertical (90 degrees to what I need to take them out) and there are plastic half-circles that seem to be holding the bulbs in place (and prevent them to be rotated I guess). The cabinet is designed in a way that only allows a good grip on one side of the bulb but not on the other (see the lower lamp — enough place for a finger below, but none above since the two lamps are meeting there)

enter image description here

My only guess at the moment would be bending the holders outwards and forcing the bulbs out this way, but I'd rather avoid it for the sake of the rent deposit.

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    BTW, what's the symptom that made you decide they needed changing? the ends of the tubes don't look burned out (the inner coating gets faded & blackened at the ends over time, which can be a rough guide to their lifespan). If they just flicker & are hard to start, change the starters first, before changing the tubes. For 'best' performance you should change them as a pair anyway.
    – Tetsujin
    Feb 25 at 11:04
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    @Tetsujin the other ends are all blackened, it was just easier to take the picture of this side
    – black_fm
    Feb 25 at 12:55
  • To remove the shorter bulb at the bottom, first remove the longer one at the top. Then you'll have room to get your fingers on both the top & bottom of that shorter bulb so you can more easily rotate it.
    – FreeMan
    Feb 25 at 13:50
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That type of lamp holder comes in two variants - push or twist. The technique for one cannot be used on the other.

The push type have sprung and caps, you push sideways on the tube which enables one end to just lift out. No twisting.
Yours are the twist type; 90° rotation, so if you can't twist, then trying to force the end caps away will just break them. Once you've achieved the correct alignment, they should almost fall out under their own weight.

There are usually two main types of twist. I don't know their true names, so let's call them 'open' & 'insert'. The 'open' type use just the grip of the outer edge on the pins to maintain tension as you twist. The 'insert' type have an inner sleeve which must be rotated with the tube pins to release. This insert, over time tends to get a bit 'burned' - not dangerously, but enough to make them quite abrasive & grip the outer white end caps. It can feel like you're trying to slide two pieces of sandpaper over each other, very creaky & 'grippy'.

With the power off, you could try getting a bit of WD40 into the gap between the white outer & the black insert. Let capillary action pull it around the back. (WD 40 is not conductive, but wipe it away as best you can afterwards.) After half an hour or so, see if you can then twist it out - note it should be possible twist either way, so give both ways a go. Very few are one-way only, so if one way seems to go better than the other, then favour it. Only once it's properly loosened will you be able to tell if it really was only designed to twist one way.

If you absolutely cannot turn it, you can break the tubes out - wrap full length in cling-film (saran-wrap) as best you can & tap the centre, hard. Then you can just pull the broken centre towards you & free both ends. Be careful, of course. That might give you a better chance at freeing up the mechanism with the tubes out of the way.

Contrasting the apparent simplicity of their design, these can be remarkably obstinate fittings to have to deal with, with little tolerance for brute force methods. Cajoling is better in the long run, but you might not be first to approach this task. If in the past, 6 different people have had 6 conflicting methods of extracting & replacing tubes, the mechanism can be really easy to completely hash up & effectively 'lock you out'. Once the tube is out you will have a better chance of seeing what state the mechanism is in.

If you absolutely have to replace the fittings, get sprung caps instead. They're far less trouble overall. Better still, swap for LED fittings. (For sake of completeness - you can get direct replacement LED tubes, but you must disconnect the ballast or take the starter out before using them.)

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  • Thanks a lot for a detailed answer. That's definitely the «insert» type. Not sure whether the symptoms match the «burnt» state, it does not feel «grindy» but rather "rotate freely within a very small range and then stop hard", but I'm going to give WD40 a try, got nothing to lose here.
    – black_fm
    Feb 25 at 10:39
  • I'm also guessing that one of the previous tenants forced lamps out without rotating and now the fittings are in the same state as diy.stackexchange.com/questions/85291/… where they have no chance of rotating anymore with the pins being bent and blocking the sleeve, I guess that would fit the «rotate a bit and then get completely block» situation
    – black_fm
    Feb 25 at 10:42
  • there's a third type with a Y shaped slot, those you twist until one pin comes to the front and then pull on the tube.
    – Jasen
    Feb 25 at 10:43
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    @Jasen - yes, I'd forgotten about those. They were the rarest I used to come across, used to be mainly on the 'mini tubes' T4 I think they were (it's been a while). Haven't done that job in a few yesrs, so some of the variants have now just blended into one memory… of fighting the %$£@!! things every day to get them out ;)
    – Tetsujin
    Feb 25 at 10:45
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    In the end, adding lubrication is what worked for me. With that and a bit more force it finally turned!
    – black_fm
    Feb 25 at 16:03
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You rotate until you can see one of the the pins clearly (which you have already done), then pull one side straight out. A few pounds of force should be all that is needed.

To re-install, reverse the process. The amount of rotation should be closer to 90 degrees, you will feel it snap when you are there.

https://www.wikihow.com/Remove-a-Fluorescent-Light

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  • Sorry, I should have bee more clear – I see the pins in the gap between the bulb and the holder and they are currently in the «locked» state, 90 degrees off what they would be after insertion. So current problem is not pulling the lamp out but to rotate it to the point where pins would align with the wedge on the socket
    – black_fm
    Feb 25 at 8:58
  • OK, maybe you haven't rotated it far enough yet. I must have misread the picture.
    – Mattman944
    Feb 25 at 9:09
  • Yeah, the problem is that it wouldn't rotate, just turns a bit and then it's as if it hits a complete block. I wonder if it somehow ended up in a situation like this diy.stackexchange.com/questions/85291/… with pins bent and preventing plastic rings from turning.
    – black_fm
    Feb 25 at 9:41
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That type of base absolutely does rotate. But they can be stiff to start.

I would advise more force.

Do not lubricate it. There is no lubricant I know of that wouldn't cause negative side-effects.

The rotating plastic guard is just there to keep the lamp from tramming while it rotates (put a few fluorescent tubes in sockets that don't have that and you'll know what I mean). However it adds a new problem: it's possible to get the 2 guards out of sync with each other when the tube is out. In that case, use a tube as a "key" to turn one.

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