Honestly just stay away from anything sold in pet stores. All they sell is overpriced junk.
RHP cannot be used with glass tanks. They need to be used with PVC reptile cages like the ones sold by animal plastics
Even with a thermostat you will need good probed thermometers. I like this one that is sold at Walmart for $12. It has 2 temperature sensors and a humidity sensor. The probe goes on the hot side directly above the UTH on the cage floor and the unit sits on the cool side.
Once again this thread has everything you need to know about cage heating: http://ball-pythons.net/forums/showt...t-Thermometers
What is the temperature of the room that the cage is in? As hard as it might be to understand your snake is at risk of being too cold and getting burned at the same time. The air temperature is probably far too low which can lead to respiratory infections among other things while the surface temperature of the cage floor will get too hot and potentially burn the belly of your snake.