Multiple tubs with one thermostat?

[Vacado]

Hey all, I noticed in some threads that people mentioned using one thermostat for multiple tubs? How does this work? Aren't you afraid that if something goes haywire in the tub with the probe, it will fry/freeze the snakes in all the other tubs? I know there are thermostats that allow you to put up to four tubs on them, and they have four probes, but I've seen people using one thermostat with one probe to run all the flexwatt in their rack system. This seems like a bad idea to me but is there something I'm missing?

v

[TMoore]

In the rack that I'm using there is one piece of flexwatt. It loops its self back and forth with each level, going across, then down a level before going across again. So in theory, that whole piece should be the same temp and so should all 5 of my tubs.

In the case that there are multiple strips it really shouldn't be much different. If all the pieces of flexwatt are the same size, wired correctly, and the probe is positioned correctly there should be no problems. The probe for a t-stat doesn't go in a tub, it should be attached directly to the flexwatt.

[ThyTempest]

If you plug in identical heating elements into a power strip, and control the power strip with the tstat, all of the heating elements should be pretty much the same temp. The order on the strip varies the temps a little, but usually it is negligible.

The key is make sure that the heating elements are exactly the same....ie...all the exact same UTH or the exact same length of the exact same flexwatt etc.

[Vacado]

In the rack that I'm using there is one piece of flexwatt. It loops its self back and forth with each level, going across, then down a level before going across again. So in theory, that whole piece should be the same temp and so should all 5 of my tubs.

Genius!!! Was this a custom-built rack? Do you have photos? This sounds like a great idea and would make temp control a lot easier (and have fewer wires). What is the total wattage of this system? Do you have any problems with heat gradients over the length of the flexwatt (i.e. is it cooler at the far end?).


I guess I'm not being clear enough with my question though. If you have five pieces of flexwatt on five tubs, and you only hook the probe up to one piece of flexwatt, that piece of flexwatt could malfunction and the thermostat would compensate for the heat gain/loss and also change the temps of all the other flexwatt pieces too. If the piece the probe is attached to malfunctions and starts cooling off, for instance, the thermostat will try to increase the temperature of the flexwatt. This will also increase the temps of all the properly-functioning pieces of flexwatt as well, frying those poor snakes. I've seen people mention flexwatt going awry, though I've not gotten any details.

The reason I'm so concerned about this is because I recently had a UTH go absolutely haywire, melting holes through itself and sparking. I'm lucky, I got home just in time. I bought flexwatt because I'm terrified of those UTH pads now, and my experience has shown me that it's safest to be able to control each heating element. The problem with that is that the Herpstat Pro (so far the only thermostat I've seen with 4 probes) is over $300.

v

[TMoore]

Its a Reptile Basics rack. The whole piece of flexwatt is about 8.5 feet in length, and I believe 10 watts per foot. So the total wattage is around 85.

There is a slight difference between the top and bottom levels in regards to temperature. I don't know if its necessarily caused by a difference in the heat tape. I think its caused more by the fact that the bottom of the rack is directly on the ground. I have seen people make a small platform to put the rack on alleviating some of the cooling.

http://www.reptilebasics.com/

With the multiple pieces of flexwatt there is a chance it may malfunction, but you can use a back up thermostat just in case the first one fails.

[nevohraalnavnoj]

I have 6 Reptile Basics sweaterbox racks hooked up to one thermostat, with a backup thermostat as well. I've never had any problems, and controlling all of them with one thermostat does make things easier.

Since space was tight this year, all I did for my temp drop was hook a rheostat in between the power strip and one rack, effectively throttling that one rack down.

One thing to watch out for, however, is that you don't exceed the rating of your thermostat. Helix's are only rated to 500 watts, so if each rack is about 80 watts, for example, that tops you out at 6 or less on one thermostat.


JonV