chiller control? DIY?

[Brad S]

My tank reached 90 last week, I threw a coil type chiller on, except it has no controller...

For now it's set on a timer, 30 min on, 1 hour off... Seems to be keeping the tank around 78-82... Nothing I can do about the temp swings though, unless of-course I can find a controller.

I was thinking about DIY... Maybe someone has a better idea than what I've planned out?

My idea is simply a home t-stat I have laying around, electronic... Spliced into an extension cord which will power the chiller when the temp goes above 78...

Anyone else?

 

[Miller]

Here is a link to Jennifer's DIY controller.

http://home.comcast.net/~jennyleep/Diycontroller.htm

 

[Jennifer]

Thanks for the plug Barry.
Brad if you choose to use the design I will be happy to answer any questions.

 

[NateHanson]

How about a 2-stage Ronco controller?

 

[NateHanson]

Oops. I mean Ranco, not Ronco! ("Set it, and forget it!" )

Ranco makes a 2-stage controller for your heater and chiller that's supposed to be really good. https://diyreef.authsecure.com/shop...d=212&osCsid=991422c1b7f1acc89b442e0bee25e34e

Or if you want to get out cheaper, and just keep your current heater control, you could get a single-stage ranco controller. I think they're more like $70.

 

[alpha0r]

I don't know what your budget is but an Aquacontroller Jr. could handle this for you and provide a lot of other cool functions too.

 

[mgreefer]

Hi Jennifer,

I love the idea of modifying a simple and cheap cooling thermostat to drive fans I understand the relay function and could easily do it however most thermostats out there now don’t have the little wire to sense temperature I think they use some kind of an electronic sensor. I don’t have a problem disconnecting it and replacing it with a water sensor from an old controller I have laying around but I cannot quite figure out which part of the thermostat is the sensor. I am sure it won’t measure the right temperature because it is obviously calibrated for its own sensor but I don’t mind comparing its reading to something else and account for the difference.

Do you know how can I figure where the sensor is in a thermostat and would that work?

Also I found a heat thermostat with an external ground sensor @HD the sensor is water proof, do you know a way to reverse the function of the thermostat and have it kick in when temp is high instead?

Thanks.

 

[Jennifer]

Hi Jennifer,

I love the idea of modifying a simple and cheap cooling thermostat to drive fans I understand the relay function and could easily do it however most thermostats out there now don’t have the little wire to sense temperature I think they use some kind of an electronic sensor. I don’t have a problem disconnecting it and replacing it with a water sensor from an old controller I have laying around but I cannot quite figure out which part of the thermostat is the sensor. I am sure it won’t measure the right temperature because it is obviously calibrated for its own sensor but I don’t mind comparing its reading to something else and account for the difference.

Do you know how can I figure where the sensor is in a thermostat and would that work?

Also I found a heat thermostat with an external ground sensor @HD the sensor is water proof, do you know a way to reverse the function of the thermostat and have it kick in when temp is high instead?

Thanks.

Thanks it was rather simple if you have the know how.

In the picture I put an arrow to show the thermistor. It was in the case buried under some hot glue. I actually put batteries in the thermostat (not hooked to anything) and started holding my fingers over certain parts on the board. I knew right away when I held my fingers over this 1 and the temp displayed started to rise.

This is a honeywell thermostat I am unsure of what other manufacturers are using for thermistors but a**-u-me it would look similar. The finger heat test would work fine to locate a thermistor. After that a little silicone some heat shrink tubing and the assembly is now waterproof. Someone else recommended dipping the new thermistor assemble in epoxy paint to water proof. I think that is a good idea as well.
Good luck LMK how it works for you. - Jenn