Why do some (versus all) of my fluorescent lights intermittently turn on?

CPT Joseph K Murdock — Tue, 20 Sep 2016 17:20:59 -0400

My question is your answer. I have a fixture of 4 fluorescent lights that appear burnt out, however, sometimes they all turn on as opposed to all do not turn on. I would appreciate your thoughts on the fix.

Response by CDR Terry Boles made Sep 20 at 2016 5:28 PM

CDR Terry Boles — Tue, 20 Sep 2016 17:28:38 -0400

One would normally see two lights NOT working IF one of the light bulbs is bad, which you can replace. Its a bit unusual to see 4 lights not work occasionally. Assuming your electric is OK and wired connections are OK...then....

I would look at the ballast, inside the metal cover down the middle of the light fixture. Sometimes the ballast can have a temperature thermostat that resets when the temps are too high. You see this mostly on 8 foot fixtures. You can replace the ballast quite easily.

On shorter length fixtures some old timey fixtures have starters and they can go bad, its a little cylinder located at the end of the fixture. They too can be replaced.

Hope some of this food for thought helps!

Response by SGM Erik Marquez made Sep 20 at 2016 5:46 PM

SGM Erik Marquez — Tue, 20 Sep 2016 17:46:13 -0400

either or both or all
connections
ballast
Tube
I dont spend money or time on my T8 fixtures in the shop any more, as each goes bad it gets replaced with an LED fixture... I buy two at a time, and keep at least on on hand for a quick swap as a T8 bulb, ballast goes out.
I've done 5 so far, leaving 9 more to go. get um on sale at sam's club, costco or Lowes / HD

Response by 1SG Private RallyPoint Member made Sep 20 at 2016 5:58 PM

1SG Private RallyPoint Member — Tue, 20 Sep 2016 17:58:07 -0400

I would bet they are not seating completely in ballasts. I suggest replacing them.