When the outside temperature is above 85 F or below 45 F the fluorescent bulb does not come on. What is the problem?

Hi, johnmheng!

Greetings and WELCOME to the site! I just moved your question that you had posted in Introductions to this topic area so that it would get the most exposure to those who are best able to answer it. Introductions is for people to introduce themselves and we try to not ask questions there.

We would appreciate it if you would return to Introductions sometime to tell us a little about yourself though, if you would be willing to do that.

I'm sure that someone will eventually come along who knows the answer to your question. However, some of the best people who know how to answer it might be asleep right now.

Thanks!

What type of fixture and where is it located? Inside or outside?

What type of fixture and where is it located? Inside or outside?
40 watt fluorescent lamp fixture is in the master bathroom connected to a silent light switch

Is the fixture properly grounded?

Fluorescent lamps will have trouble coming on when they are cold. Not too much you can do about that, Make sure that the ballast is rated for the fixture. There have been some changes in which some energy efficient bulbs have a hard time starting without changing the ballast.

You might try a little petroleum jelly or dialectric grease on the tube connections to see if moisture and bad connections could be causing problems. And starting is dependent on having a good ground to the reflector.