Heating Problem or is it?

[Midwest Morphs]

I have a 32Qt. Rack from herp enclosures. The other day I was told to move my probe to the flexwatt instead of the tub. I did this but when the Helix was set to about a hundread the tub was still only 82. My ambient temps are around 75 all the time. If i place the probe in the tub I can maintain 92 all day long. Is there something Im doing wrong here I went and got foil tape to tape the probe to the heat tape, it just will not heat it up enough it doesnt seem.

Thanks
RK

[JLC]

A couple of things may be going on.

--When you have the probe in the tub, you don't know how hot the flexwatt itself is actually getting. So it could be much hotter than 100* in order to get the tub temps to 92. However, if this is the case, I would suspect either you have a somewhat thick layer of substrate that it is having to heat through...OR it is open beneath the flexwatt (at least partially) and you're having heat escape below the tub, making it heat ineffeciently.

--The other thing could be that you're putting the probe in an area where the heat is getting trapped around the probe and the t-stat thinks the whole pad of flexwatt is warmed to 100* when really it's just that little pocket of trapped air around the probe.

[muddoc]

As Judy stated, just for your own knowledge, I would use a thermometer, preferably a tempgun, to measure temps on the heat tape itself while the probe is in the tub. My bet would be that the heat tape may be in the 110 to 115 degree range. If that is the case, you are sitting on a fire waiting to happen. I don't recall what size heat tape you are using, but with ambient temps so low, I would suggest moving up to some 11" flexwatt.

[Midwest Morphs]

The tape looks like 4 inch tape. I used the tempgun and its 105 on the heat tape iteself.
The tape in this rack is resessed so I dont know how i would really put 11in. where the tubs would not just slide on the tape.

I do have aspen should I try to remove it and put paper down?
And taping the probe down i need to make it so the tape fits exactally or is there another way to place the probe?
As for heat escaping its a closed side rack, resessed tape and has just a 1/4 air hole where the tape is at.

RK

[Midwest Morphs]

Anyone?

I dont want to take a change of doing harm to them, and want to get their heat squared away. As of right now they have good solid 92 degree heat but I dont want to over work or damage the tape.

[JLC]

Given what you've described, I would guess that your substrate is too thick. Try using just two sheets of newspaper or newsprint...OR...just a very thin layer of aspen. They don't need it for cushioning...just to absorb waste when they make a mess.

I'd say 105* is at the high end of tolerable, and hopefully, with less substrate, you can get that down another few degrees while maintaining the temps you want. Just make sure that the actual floor of the tub is at the temps you want and not sitting at 100+ degrees.

I think you're really close to getting everything dialed in just right.