Need some help with flexwatt

So i wired up the flexwatt on my rack and hooked it up to my herpstat pro but now have a little issue. The probe on the heat tape says its at 92 but none of the tubs are going above 77 degrees... i attached the probe to the heat tape with a strip of aluminum tape, could that throw off the reading? Any help with this problem would be greatly appreciated.
Thanks

First things first.

Remove the tubs.

Place your hand on the flexwatt.

Is it warm?

Grab an IR thermometer, and read the flexwatt's surface temp.

One thing that might be affecting the probe is placement & tape, like you said. The tape will act somewhat like an insulator, trapping a fair bit of heat around the probe. One way to secure the probe is to put tape over the wire connecting it to the herpstat unit, but not over the probe itself.

Also, some probe placements just end up being warmer than other more ventilated areas (in the tub, or places further away from the heat tape for instance). Ever used a heat lamp? Surface temps of an incandescent bulb or CHE can be REALLY hot, but only a few feet away have an air temp that is pretty reasonable. It's important to consider how heat dissipates (or collects in insulated areas).

So i took out the tubs and felt the flexwatt and it was lukewarm at best, took the tape off the probe and taped down the wire so it is now just sitting on the flexwatt and the temp that the herpstat is reading dropped to 78. Now when i touch the flexwatt it is a lot warmer. I would use an IR thermometer if i had one but don't... so hopefully the only issue was that the aluminum tape was trapping the heat. Thank you so much for the help