I would use electrical tape as it suggests in the instructions. 72 is too cool I would suggest you heat the room to a stable temp perhaps 78-80 range. The al. tape may cause the probe to to be infulanced by the air temp and cool off reading below actual temps.

I use this method I place al. tape on the heating element (about a 2 inch long and 1.25 wide) (it helps transfer heat to the probe and even off the variations in the flexwatt) in the middle of the centre rack slot flexwatt. I place the probe on the centre of the al. tape and use electrical tape to cover the probe and al. tape. My method it works for me.

Some herpstats (not all) have a mechanical relay that have the ability to set a low temp and high temp turn off points. If the probe is pulled loose of the heat and dangles free the herpstat with this feature enabled will not continue to try to heat the rack but power down and start beeping a warning. If this is not enabled the unit will record too low temps and max out the heater in an attempt to heat the probe to correct temps again (when the probe is pulled off the heat this will never happen) this can cause a 'run away' heat and the temps will sky rocket. A failsafe is a second T-stat usually probed on the top (hottest) slot and it will measure the elevated temps and kill the power to the primary t-stat. In practice the same thing as the mechanical relay will do. (only the HS1 and better have this and then it needs to be set up in options)

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