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The house that I rent has an old (c. 1955) stove. There is a fluorescent fixture inside the back console to provide light to the cook surface, which takes a 30-watt T8 bulb. When this fixture was working, it was operated by a push button; to turn on the light, you had to press & hold the push button for a couple of seconds (until the ends of the bulb glowed faintly) and then release the button.

Recently, my wife tried to turn on this light to make dinner, and told me that there was a "bright flash" and the light didn't work any more. I went to our local big-box store and bought a replacement tube. I installed it, turned it on, and there was a bright flash and then the replacement tube didn't work either. Both tubes had something audibly rattling around inside them after their failure.

So something is obviously wrong with the lighting circuitry inside the stove. My questions are:

  • What is the likely cause of this failure mode?
  • Can I replace the fluorescent bulb with an LED tube replacement such as this one? Or will the circuitry fry that too?

I did manage to dig up an old service manual for this range; the wiring diagram for the fluorescent fixture is below. My main goal here is to avoid calling in the landlord/repair people if it's something I can fix myself, but I do not have the expertise to go mucking around with the internal wiring.

enter image description here

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    Replacing the tube you are allowed to do. To work on the insides your landlord must get a licensed electrician/appliance repair person in.
    – crip659
    Commented Oct 27 at 13:40
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    @crip659 Maybe. In a rental, electrical that is part of the building nearly always requires a licensed electrician. And I would argue that would apply to the ballast of a permanently attached light fixture. Not so clear to me that the same rule would apply to ballast (or possibly the capacitor shown in the diagram) in an appliance. The lease may or may not clarify things.
    – manassehkatz-Moving 2 Codidact
    Commented Oct 27 at 14:27
  • What looks like a repair that you think you could do yourself, could go wrong. If it would, you could be in for a very unpleasant experience. Even if you would successfully repair this, you would forever have liability in case something would go wrong later. Report this to the landlord. DO NOT ATTEMPT THIS YOURSELF.
    – Jim Stewart
    Commented Oct 27 at 15:59
  • To clarify: I do not intend to do anything to the internal wiring of the stove myself; I will leave that to a professional if it is necessary. I posted the diagram in case it could help people more knowledgeable than myself answer the two questions I posted above.
    – Michael Seifert
    Commented Oct 27 at 16:31
  • And if the answer is "any LED replacement tube would require internal rewiring" then that should be posted below. :)
    – Michael Seifert
    Commented Oct 27 at 16:34

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What is the likely cause of this failure mode?

being an old 1950's style fluorescent... google fluorescent light history... it used a magnetic ballast, and a starter given your description of glow during pre start, and the capacitor per your diagram for power factor correction because the magnetic ballast results in induction.

the failure of the bulb just flashing and popping (immediately?) on start and going dead sounds like a failed capacitor to short. But I wouldn't know without testing specifically. In addition the other cause being a failed ballast not regulating current.

The purpose of the ballast is to be a current limiter in the lamp tube. The fluoro. tube requires a starting voltage of a high voltage but once the gas inside the lamp is lit voltage & current is reduced, by the ballast, and will depend on size/length (wattage) of the lamp. The small light you have run below 100v and around 1/3 amp (i.e. 30 watt = 100V x 0.3A) If the voltage & current is not reduced the lamp's electrodes inside burn out. Will a ballast cause the bulb to fail immediately on start like you described, I don't know it's been a while since I've messed with old fluoro stuff. Smart thing to do is call someone who still deals with this and ask, for example...

https://viribright.com/pages/led-tubes-ultimate-guide-to-replacing-cfl-tube-lights

Can I replace the fluorescent bulb with an LED tube replacement such as "GE replacement 30-watt T8" Item #2565469 Model #93129785 $14 lowes

yes, that's what they are for.

https://www.led.com/inspiration/picking-an-led-tube-replacement-essential-facts-you-need-to-know

https://www.waveformlighting.com/tech/everything-you-need-to-know-about-led-tube-lights

https://leanlight.com/pages/led-tube-types?srsltid=AfmBOoo50QiJwqzfZQzXIJEzxPEx4PQEK50tZw3cEQQYKgIQsqvM0o5x

Type A LED - Ballast compatible as opposed to type B ballast bypass

you GE replacement from lowes notice "Type A tube type" and "ballast compatibility = electronic/magnetic".

If the capacitor is a failed to short, then will running a ~12 watt light through it be or become a problem? Best thing to do is do a ballast and starter and capacitor removal (not a complicated "rewire") and mark it as such to use an LED retrofit and will solve all possible problems. But simply using a LED retrofit like you link would not be "fried" given your problems with your existing ballast or capacitor, it simply would not light if the ballast was failed open and there was not current. If the ballast is failing to regulate well type B's are designed to operate on full 120v and type A's the same in addition to accounting for the voltage/current reduction by the ballast.

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It's probably the ballast, but the comments are all on point.

I have replaced all my ballast driven shop lights with LED ones and a few desk lamps that had your push and hold to start fluorescent lamps with LEDs. They all required rewiring. I own all those things, including the home they are in.

IMO, in a rental all you should ever repair is minor damage to walls. No electrical, no plumbing, ever.

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