Two flourescent light fixtures in garage, each with 2 quantity 4 foot long flourescent light bulb tubes, each fixture has a ballast pack in them. 1 has never lit up in 20 years. Last night I messed with it, redid wire nuts, put NEW bulbs in and it worked. Then the other fixture that has ALWAYS WORKED stopped turning on, but the one I hadn't used in 20 years still is working. If I go re-seat the bulb tubes in the light that is OFF it turns them on. Then both fixtures are lit with all 4 bulbs fully bright and not flickering. Then I turn off the light switch and turn it back on again and the damn fixture that ALWAYS WORKED religiously for 20 years still won't turn back on until I re-seat the light bulb tube again. If I remove the bulbs from one fixture the other fixture always works. This is over 14/2awg wiring and to my knowledge isn't shared with anything else electrically. Does the light that always worked need a new ballast or are the new flourescent bulbs messing with the setup? Each bulb is 40 watts, 80 watts per fixture.

the fixture is rated .675 amps 60 hertz and 120 volts which i have calculated equals 81 watts, which would be right at 40 watts a bulb.

After fiddling with them a lot again tonight, i've noticed that the new bulbs turn on much faster than the old ones do and when both fixtures did work in tandem, each successive off/on cycle saw the ole faithful light fixture lose more and more light each time on/off. In the end i realized that the bulbs i got are quick start bulbs..... so maybe if i got a new set of bulbs for the ole faithful fixture to match the fixture that hasnt run in 20 years, maybe they'd both work again??? Its almost as if the old fixtue with the ole bulbs isnt getting enough "startup surge" current to fully light up initially. i have checked the voltage at the fixture-we-didnt use-in-20 years and it is getting a full 120volts, but i didnt check voltage at the ole faithful fixture that now wont turn onand is being mean.

new bulbs?

 

The old T-12 tubes were 40 watts. Now they are lower wattage. T-12's are being phased out of production and will be hard to get soon.

Here's the real problem.... fluorescent tubes have mercury in them. The mercury vaporizes and the gas inside the tube becomes conductive and you get light. The mercury content has been reduced in all tubes including the current T-12's. The older ballasts don't have enough voltage to always strike an arc in the tube due to the lower mercury levels.

The newer electronic ballasts are much higher voltage.

I don't have too much patience with old T-12 lamps. I've converted all my fixtures over to electronic ballasts and type T-8 tubes. T-8's are 32 watt tubes. You can use the original tube sockets when converting from older, large style T-12 tubes to the thinner T-8 tubes.

 

Ok. Well, so you don't think that I can get new T12's to match the other new T12's and see if all 4 tubes will come on?

or

do I just need to go ahead and convert to T8 32 watts to get it to work, "right now"?

If I could get the old ballasts and T12's to work today, I'd rather do that because it looks like I'd have to remove the entire fixture and connected wiring points in the attic to replace the T12 ballasts and perhaps even entirely new fixtures too.

 

The problem is the tubes themselves as I explained above. You may be able to get new ones and have them work and maybe not.

The ballasts and lamp wiring should be available from the tube side of the fixture.

 

I mean i can see where the bulbs clip/snap in, but and I can slightly move the plastic connector with the metal connection points in them ... side to side, but I don't see how I can remove them without taking down the whole fixture.

I am on my way to the store. Going to buy 2 more new tubes and 2 new ballasts and 4 T8's as well. If the new T12's work, i'll be golden and if not then I'll be ready with the T8 setup.

FYI - I was able to find both T12 and T8 ballasts at Wal-mart supercenter the other day.

 

Go with the T8's. They will save you money.
I worked at a 21 story hotel that spent $250,000 changing every light to T5 and T8, they saved that much on their electric bills after 2 years.
Granted you house is not filled with thousands of fixtures, it would be worth your while to change over to T8's and CFL's/LED's.

EDIT: You should take a look for incentive in your area. Here there is a small tax break from our government for switching over to low energy bulbs/fixtures.

 

In our area the tax incentives are geared to toward businesses and large power users.

 

I fixed the issue staying at T12's, but replacing all 4 tubes with NEW ones.

All 4 lights then came on dependably every time...... but then tonight I tripped a breaker off of apparently a measly accidental touch of two wires with only 1.5v left in them (thought it was ghost voltage; had turned a breaker off)... and that breaker happened to share the garage lighting. Oh Brother...... after we turned it back on the original light that has always worked started not coming on again.

I wonder if the power surge/tripping of breaker messed with the ballast or the connection point ends of the new bulbs.... because after fiddling with positioning of how the tubes are held in their metal connectors for power, the light now comes on consistently.... but before I'd found the "sweet spot" the light that had always worked, fought me hard during turning it on/off several times.

Before the breaker tripped, the lights were SOLID.... GOLDEN..... came on both sets of fixtures every single time.

 

So, I throw a weight belt at the light fixture and the flourescent (new ones) tubes turn on..... Now most of the time i flip the light switch and the tubes turn on, but maybe 30% of the time they don't turn on ..... but each time, jiggling the bulbs makes them turn on.

Whats that mean? Ballast probably?

I know ya'll said go T8's... but lets face it..... T12's are bigger, more watts = more light. I'm just going to let it ride till it forces me to replace them.... but anyway... based on the above description... ya think the ballast is going bad? I have a new T12 ballast just in case.

I see no way (unless there's something I don't know about on these 4 foot fixtures) to access the bulb socket connection points without removing the fixture. Is that about right?

 

When you jiggle or turn the tube you are opening up the filament circuit and the tube voltage goes up and the tube lights.

T-12's = bigger =more watts used and less light output.

T-8's = smaller = less watts used and more light output.

Since we have no idea what type of fixture you have it's hard to comment on the exact method used to replace the ballast and get to the wiring.

If it's a surface strip.... the cover snaps off.
If it's a recessed fixture..... the cover between the tubes snaps off to access ballast.

 

I like the weight belt approach.

 

LOL Mr Awesome. Ever since then... lol.... the lights have been coming on 95% of the time. LOL

PJmax - I would've never believed that about the lighting output difference on lower wattage. Well, now having 4 T12's as opposed to the 2 old ones we only had for years..... the garage looks like a whole different place now, so I'm fine with the T12's for now. Gotta get a lot of other things out of the way before replacing fixtures.

FYI they are the recessed fixtures from your description. I snap off the middle just fine and easy and can see the wires/ballasts etc.. but I don't see how I could remove the wiring from the fixture tube connector clips without removing the whole fixture.

I appreciate everyone's time and help. Thanks. So far so good on the 4 T12's running.

 

When you reballast a fixture you basically cut the wiring right at the old ballast and reconnect them to the new ballast.

 

Oh.... I was stuck thinking of not wanting to add more wire nuts/connections into the circuit, but I guess it doesn't matter as long as I get the right light output. I see what you are saying now.