Sounds like brain damage. I hope not though! Do you have the RHP on a thermostat? How else did it spike? I don't understand how anyone can run a heater without a very carefully setup thermostat.
A few years ago, I got my first uth and didn't know that thermostats were necessary. Heck, I didn't even know they existed and figured the mat wouldn't get hot enough to do damage. Luckily it just cracked the bottom of the tank and didn't hurt my snake