# ? on how to calibrate Eheim Jager heater



## comet (Jun 10, 2006)

Ok... It's 10pm and I see that the temp has risen in my tank by almost 5 degrees and all other tank temps are running normal. So, I pulled the plug on the Visi-Therm heater and put in a new 100 W Eheim Jager heater.

I moved the blue dial to read 80 degrees F where the red arrow is now pointed to. Temperature when plugged in was 83.7.

Read the instructions on how to calibrate in case it became necessary and I am at a complete loss on what to do.:help:

Can someone please give me detailed instructions on what to do if;
1. The temp. in the tank is now too low
2. The temp in the tank is now too high.

I'll probably be up till 2 am watching the temp. in this tank!

Pamphlet instructions;

Recalibration
If, after a day or two in operation the setting scale does
not correspond to the water temperature, follow the
following procedure to recalibrate the heater:
Switch off the heater and unplug it from the main
supply.
Measure the water temperature with an accurate
thermometer
Turn indicator arrow (red) to point to the measured temperature.
Set the desired tank temperature with the temperature selector ring(blue) . ?


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## accordztech (Dec 6, 2004)

After letting it sit with a stable temp for a day, then adjust the red dial to the temp. 

I had issues calibrating mine. That was cause the sealed lid and the light heated up the water and threw off my calibration.

I also used 2 thermometers. One digital and one analog to Make sure i was accurate


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## comet (Jun 10, 2006)

Thanks for the reply. After _calming_ down my panic of waking up to a 62 degree tank, and further reading about the instructions, I figured it out. :redface:
I do see how room temp and lighting heat can mess with your calibration. I'll just calibrate it after checking the tank temp. the same time each morning. 
This heater, set at 80F is keeping the 20 long tank at 78.6 since yesterday evening. And yes, you will need a trusted thermometer(s) for this.


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## accordztech (Dec 6, 2004)

My room goes from 70 to 80 in the day. But my lighting on my sealed canopy heats my water up by quite a bit. I did a test with the cover on and off and monitored the temps.


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