DIY Fan Thermostat (ugly, but works!)

Re:

The big problem with above thermostat, is that works off air temperature, instead of water temperature.

Thought pretty practical as was running in enclosed sump cabinet where air temp is pretty much same as water temp. So fans would kick on at right temperature.

PROBLEM: Air temp in cabinet cooled off much more quickly then water temp, so was always kicking on and off. After a while, it became primarily as a high water temp gauge, as when it went off I then would turn on fans full time.

SOLUTION: "Tangster" gets credit for idea...he said to try attaching thermostat device to side of sump, then tape over coils against side of sump so they would react on temp reflected from side of sump.

Tried it, and was not very satisfactory. May have to due with my sump being a plastic rubbermaid tub. :-/

Thinking about it a bit, I came up with following idea and IT WORKS GREAT!

Take copper wire long enough to make coils on both ends. One set of coils small enough to go in a test tube, the others just small enough to fit inside the coil sensor on thermostat.

Insert small coil in test tube. Fill with clean water. Cram in soft "Duct Seal" first couple of inches of test tube containing wire and water. Then cap entire end using plumbers putty. - You want to make sure tube is absolutely water tight as this end will be underwater in sump. (and we don't want any possible exposure to Cu poisoning )




Next, placed large copper coil inside sensor coil and sealed in with "Duct Seal."

Insulated Sensor coil all over with Styrofoam shipping "popcorn" - then covered that whole mess again with the Duct Seal...looking like,



After putty hardened into the tank went the probe.

Took a few hours for temp in device coil to warm up to tank temp...but then began to work perfectly based on water temp, not air temp... Have "turn on" temp set to 81.5 degrees/ does not take long for the 7 fans I have hooked up to it, to cool tank water to below 80 degrees...

Pretty simple way to make a great device work as desired!

 

Very cool! I should make me one of these baby's!

 

Thank you! I have been trying to find a devise that would do just that! I will be ordering the thermostat from KKontrols shortly!

 

Just a report - my fan thermostat is working great!

Kicks fans on (7 of them) when tank water gets to 81.5 degrees (very exact) --- does not take long at all for the tank water temp drops below 80 degrees...whereupon thermostat turns fans off.






Anyone else try one of these things yet?

 

Tangster just put one together for our tank. Works like a charm

 

Great thread Scott.....Karma to you!!!

 

Man you are too much! that is exactly what I am looking for, thought about using one but didn't exactly for that reason, works in air and needs to work in water. Thanks you for this and Karma to you .....

EDIT: and just so you know I just ordered one...