Hydor Theo heater calibration

[outdrsyguy1]

I have 2 hydor theo heaters (both 200w). Ones 2 years old and one's maybe one year. They now run 80+ at their lowest setting (like 70F on the dial). I can't figure out how I could reset the dial so I can turn the heater down more (it's capped at 71).

Suggestions? Can I pop the top off and turn it and then stick it back down or will it break it?

I've checked the temp with 2 different thermometers and it's definitely a heater issue.

here's a link to what it looks like

 

[axio]

I'm not really sure if popping off the top of the dial like that would work... but some one else might be able to answer that better then I. Honestly that might be something that best asking Hydor directly.

Either way I would be VERY nervous even using a heater that is that far off on the temperature. Let alone one that you would need to take a apart to make work properly. Those Theo heaters are historically not very good heaters. Lots of complaints online about them overheating like crazy.

If you are able to I would recommend replacing them. Look into something like an Ehiem Jager. The Jager is able to be calibrated and reset to the right temperature if it ever goes off.

 

[grouper therapy]

I say use Ranco temp controllers. I have never trusted any heater dial/controller. I would think you would have connections to get one

 

[porpoiseaquatics]

grouper therapy;1060273 wrote: I say use Ranco temp controllers. I have never trusted any heater dial/controller. I would think you would have connections to get one

+1. Or any controller really. Never trust the dial on a heater.

Another component to your question...if you pop the top off to "reset" the dial, it will probably never reseal and thus leak which you know where that will go. I've read many articles about submersible heaters and the one constant is even though they say submersible, to never allow the dial to be underwater. It will lead to premature failure. I've made sure that both of my heater's dials are above water and they have worked flawlessly now for 3 years. Previously, I never had a heater make it a year.

I'd dump them and go with a better brand. Eheim is probably tops in my book.

 

[outdrsyguy1]

Thanks for the input everyone. I have 3 - 800w heaters I can use once my current tank gets moved to the basement along with the apex. Interesting info about the dial underwater. Both of these have always been totally submerged which definitely gives weight to the premature failure theory. I'll just make things work till I get my controller down there. Maybe I can get some folks to come help me over the holidays