Sounds to me like your UTH was defective. I used a dimmer on a UTH for my gopher snake for quite awhile and never had a problem with it. All that being said, if you've got flexwatt and t-stat on the way, then it's a non-issue anyhow. I consider dimmers to be a "better than nothing" solution if you can't afford a t-stat.Originally Posted by lillyorchid