20 Gallon Tank Eheim Thermocontrol stops working frequently

[Cherryx]

I love Eiheim products but I'm not able to find much help on this product from their limited manuals. Most of the website downloads are in German. My local store guy isnt helpful. Can anyone with experience using this product help me with this strange problem? The heater stops suddenly. Then if I unplug it & change the temp, it starts working again. I notice the interruption only when fish look a bit uncomfortable as plants hide the indicator. Is this because I didnt calibrate it properly? Can anything be done Or should I return this product? It's been over week since I bought it - the store said 3 days for returns only. Thank you in advance!

 

[Charlie’s Dad]

I would encourage you to return it. By doing so you open a window to research it at your pace and not on the clock so to speak. Just making a suggestion.
Merry Christmas!!!!
Stay safe!!!!

 

[Dechi]

You mean it just completely stops working ? It’s not just shutting off because it’s reached it’s temperature ?

 

[Cherryx]

The water is much cooler than the temp I set it in. So its not normal. Or that it turns off at the set temp as usual & never turns back in as temp drops. The store guy says it cant be returned given its over a week. Now I need to figure how this warranty thing works. If anyone knows how to reset this thing in such case, I'd be tempted to try it. Cant see any resource at all on this model.
Merry Christmas!!!

 

[Dechi]

Cherryx oh, it’s an Eheim ! They work fine once calibrated but the process itself is a pita... There are lots of videos online that shows how to do it.

I bought a Eheim recently and I kid you not, it took me about 2 weeks to get it to a usable state. It’s off 3 degress but it’s working steadily. To make sure it wasn’t going to fry my fish, I bought an Inkbird 308-S and it’s the best piece of equipment I’ve ever bought ! It’s a heater controller; you plug the Eheim in it and it will turn it on and off depending on the temperature you want.

Here’s a video on how to calibrate your heater :

 

[Cherryx]

Thank you Dechi. This is massively helpful. The video explained it neatly. Guess I went super specific on the heater name when searching and didnt realise the same model is named differently in the US. I've calibrated it now. Hopeful that fixes it. And I checked on inkbird - really solid product, not available here. Thsnks again!