Quote Originally Posted by kitedemon View Post
The manufacturer recommends an air space so I would suggest that that would be prudent as they know their product better than anyone else does. http://www.calorique.com/pdf/PetWarmingElements.pdf

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this set up inverted would be fine too.
That's talking about running them unregulated. And just them covering themselves for when people run them unregulated and they burn up.

If the thermostat probe is attached directly the the heat source there is no way for heat to build up. The thermostat will simply send less power.