Linda,
. A rheostat and a thermostat are both devices for controlling the flow of electricity. Actually thermostats are used to control any energy source (steam, fuel oil, electricity etc.) to a heating or cooling device but that is a larger discussion than what we need here. A rheostat controls the electrical flow by using variable resistance. The rheostat is a rotating, or in some cases sliding control which the operator sets to the level that they want. Rheostats are used in all sorts of electrical applications. The one you are probably most familiar with is dimmer switches for controlling the light level in room lighting. Because of this rheostat controls used in the herp hobby are often called dimmer switches. If your snake room does not have large temperature changes a rheostat can provide adequate control for your UTH and flexwatt. Rheostats are also adequate for snakes which can tolerate large temperature changes. Using a rheostat you will have to work a little to set the rheostat and then check the cage temperature and adjust as required. If your snake room has large temperature changes you will need to use a thermostat to provide safe temperatures in the snake cage. There are several different kinds of electrical thermostats. Line voltage thermostats use the full voltage of the power source to operate the thermostats and then they provide the full line voltage to the heating element. This would not be good for reptile heating because most of the heating devices we use, including your UTH and flexwatt get too hot when supplied with full line voltage. The better thermostats used for herp heating use less than line voltage to control the solid state electronics of the thermostat which provides some protection for the thermostat to not fry itself. They also provide less than full output voltage and this provides much safer control of the heating device. The best reptile heating thermostats provide proportional pulses of electricity to the heating element and this is a very energy efficient and safe way to control them. So bottom line is, if you have stable snake room temperature you can use an inexpensive store bought or even more inexpensive homemade rheostat. If you have larger temperature changes in your snake room you need to use a proportional thermostat which will cost more money. I highly recommend the thermostats made by Helix controls and the Big Apple proportional thermostat. There are probably other good ones out there, look for the word proportional in the description of the thermostat. The Big Apple proportional can be used to control the heaters for several cages and is simple to use. The Helix thermostats are available with more options for providing control to larger numbers of cages. Night time temperature drop capability is standard with the Big Apple proportional thermostat and available in the Helix systems. If you want some additional fire and overheat protection you can use both a rheostat and a proportional thermostat. If a thermostat were to fail it could provide full power to your heaters and overheat the cages killing snakes and/or causing a fire. It has happened to people I know. If you have the rheostat plugged into the output side of the thermostat and the heaters then plugged into the output from the rheostat you would have only the power level you had set on your rheostat rather than full power going to your heaters.
Jeff
>>I want to more precisely control the uth and flex-watt for my enclosures and don't know the differences in the 2 products. I don't want to spend extra money on a temp probe because I am already using thermometers and a temp gun. In a few weeks I'll order 2 boaphiles, but they want 100$ each for thermostats and I don't want to pay it. If I had to I would, but isn't there a safe and cheaper way to do it? I'm not an electrician, but I can follow instructions.
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>>Any suggestions would be appreciated. I may just buy something online anyway. I'd rather save a few bucks and buy a third boaphile.
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>>Linda
