I didn't know humidity could affect them. They are a sealed glass tube with gas in them. I know temperature affects them but never heard of humidity.
I have 4 out of 8 double fluor lights in the shop that reliably do not start in high humidity. After 20 years playing with fluor lamps up to 10' long in the sign biz (running 6 lamp ballasts w/8')... all I know is they do that. Drives me nuts when I really need light and they feel like doin' that... I suspect it's contact corrosion, making the start up not quite enough to jump the lamps.
I have an old four footer double tube in the basement workshop that does the same thing. Usually, comes up to brightness after I fiddle with the tubes a bit. Sooo-I think Stinny may be onto something with his suspicions.
I have one over the kitchen sink that I have replaced the tube, the whole fixture and the wall switch and it still doesn't like to start in the Summer on the first try. Replacing it with something else is on my no-rush things to do list.
Just talking about this today at work for lights above our tanks. We have 9 fish tanks that each hold 700-900 gals of water. My resident electrician brought this up. http://www.homedepot.com/p/Lithonia...Fluorescent-Fixture-XWL-2-32-120-RE/202034431 Gary
Yup, the enclosure helps a lot. And sealed, even better. My 4 garage lights added a 5th today... that won't start. It's been raining most of the day.
My kitchen with no windows, is drop ceiling light fixture above,, I have another light above the sink, but that Doesn't cut it, have to remove clear panel to screw with it, maybe I should get a new fixture?
Just for curiosity I grabbed a chair and wiggled the tube in this one over the sink when it wouldn't start this morning. ( the tube ends just glow orange) Fired right up. As far as I know the first fixture that was here didn't act up for 40 years. It didn't act up for the last ten for me. I had dozens of four footers in the shop. Never had to wiggle a tube. Hundreds of fl fixtures in several factories - never had to wiggle a tube. ( maybe that's what the maintenance guys did all day ) Now I have two ugly fl over the sink fixtures, one old, one new that are perfectly good just need to be smacked when they mis-behave. Yard sale. note to self: sometimes it is OK to smack things.
Yup, that wiggling moved the corroded contacts just enough. Maybe you need a stick you can swing at it, when you turn it on...
Me too! 4 double 4 footers and in damp weather 2 barely try and flicker a bit and glow at the ends but the other 2 work ok. I've gone up and wiggled them and sometimes - bingo. I always attributed to contacts getting corroded a bit. Think I will take the two lazy ones down and clean the pins then turn off the light switch and steel wool or emery cloth the slots a bit - reassemble - say a prayer and go back and switch them on. Let the be LIGHT ... please.
