I recently got a heat lamp for my ribbon, Percy. It usually stabilizes at about 84 degrees on the warm side and 75 on the cool side and stays that way all day. However, last night while I was watching a movie my sister came and told me that when she had gone into the spare room she could smell plastic melting. The heat lamp had gone up to almost 100 degrees and was apparently melting Percy's fake plant! It had been on for about 3 hours longer than it usually is, but it's usually on for 12-13 hours without going past 84. How do I keep this from happening again?!