If switch is electric, it might not be rated for type of bulb. Check rating label for switch... try incandescent bulb. Otherwise there might be short circuit causing bleed-over of power going to light bulb. http://waterheatertimer.org/Troubleshoot-household-electricity.html
Gene h
If you need further help, I’m available over the phone at https://www.6ya.com/expert/gene_9f0ef4df2f9897e7
Answers & Comments
If switch is electric, it might not be rated for type of bulb.
Check rating label for switch... try incandescent bulb.
Otherwise there might be short circuit causing bleed-over of power going to light bulb.
http://waterheatertimer.org/Troubleshoot-household-electricity.html
Gene h
If you need further help, I’m available over the phone at https://www.6ya.com/expert/gene_9f0ef4df2f9897e7