I believe that I might a need a little help with mine. I built one of these about 3 or 4 weeks ago. A few days ago I put a half cup of water in my little beer fridge (wife doesn't like me keeping all my beer in our kitchen fridge). Anyway, I let it sit there so that there would be a steady temperature and wanted to test how accurate this thing is before i buy my chest freezer for fermenting this weekend. This morning, i put the sensor wire in the water, then put a digital thermometer i brew with in the water. Left for work! Got home and decided it was time to check it and i was shocked to see that the two were about 25 degrees different from each other. I figured that this couldn't be right, so i filled the cup up full, and let it sit for about an hour. (cooking thermometer sensor is a little longer)
First picture shows the difference in the temps. (yes my fridge is a little cooler that this, but this is after i filled the cup all the way)
The second picture is the back of my temp controller. I followed android's wiring that can be found on the first page. The only thing i can think of is the 3 / 4 slots on the controller which is my question. What does it actually mean on the 4th one with the special symbol? If i look at the sensor wire, there is one with writing and there is one without writing. The one with writing is going to the 3 slot. Is this correct?
If it is, this worries me because that means it is very possible my cooking thermometer is off and that sucks because i just used it to brew a few weeks ago
Any help would be greatly appreciated!