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Old 12-20-2010, 04:04 PM
omerizm omerizm is offline
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Join Date: May 2010
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Quote:
Originally Posted by one800fish View Post
Is there any such thing as a thermostat with a probe that can be placed in the reservoir and be set for say 72 degrees and only run the pump until it cools?
I don't suppose running the solution thru a fan cooled radiator (like on a auto only smaller) would work ?
If I could find a thermosat like that the pump and the fan would'nt be running constantly.
Idunno, just asking
Hello one800fish,

Of course there is. The one I use to control my cooler works exactly as you described. Here it is:

Enda

And this is the sensor that I connect to it:

Enda

Don't worry about the brand and model. These type of devices are pretty much all the same so you can search and find a manufacturer in your country and purchase one. You don't need to buy it and have it shipped from accross the world because it will probably be more expensive and you will find it hard to get it fixed in case it brakes.

These devices work basically like this: You put the sensor in the medium you want to control, in this case you dip it in the nutrient solution inside the tank. Beware that there are different types of sensors for liquids and gases and also for different temperature ranges. You need to get one suitable for water. My controller works between -60 to 150 degrees Celsius and my sensor measures up to 150 degrees Celsius and it is for measuring liquid temp, so its good for me. By the way, some thermostats are used for cooling and some for heating but nowadays almost all digital thermostats can be used for both. You have a power input in the thermostat, connect it to your power source with a cable. And you have an output, there you want to connect the device you want to control, in this case a pump or fan or whatever you like. There should be a manual that comes with the device that explains the connections. Also from that manual you can learn how to set the controller to a desired temperature and adjust hysteresis and stuff like that. In cooling mode, it basically powers up the fan or pump or whatever when the temperature exceeds a certain point and it cuts the power when it drops below a certain point.

Say that your set temperature is 72F and hysteresis is se to 3F. it will power up the pump when temp exceeds 72+3=75F and it will stop the pump when temp. drops to 72-3=69F. You want a few degrees of hysteresis because you don't want to turn your device on when temp hits 72 and off when it drops to 71, in which case your pump would break from a non stop on/off abuse.

Cheers
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