Today I got home from work around 12 am and when I entered my room I smelled burning plastic quick checked my 2 racks and didn't notice anything strange. Just figured someone in my house burned something with plastic. Went to bed and woke up around 5 am and still smelled it. Took out one of my racks and noticed the back was oddly hot so I took out all my racks and unplugged my thermostat which I've never altered for 2+ months. While taking out all my snakes my puma managed to escape and found her after about 20 minutes. Put all my snakes in temp homes while doing this and noticed the bottom of 2/4 tubs had holes burned through them. The other two had none. The top two tubs were the ones with burns, it even burned a hole in some of the rack. I didn't make the rack or anything bought it already made with heat tape already installed with the tubs for it had my thermostat set to 93 and never touched it after that. Been good till today no idea what caused it but glad I figured it out before a snake got hurt. The heat seemed isolated though when I checked the first time I couldn't feel any abnormal heat from the front-center.