My existing fermentor is a SS Brewtech Chronical - Brewmaster Edition with a FTSs controller. The controller powers a pump that is immersed in cold water. The cold water is in a cooler box with ice bricks.

The problem that I ran into was that the pump was working really hard, and thereby heating the water. Long story short, I walked in to see my beer at 25C.

Because my controller does not have a heat cut-off point, I decided to over-engineer the solution.

Solution

1. Connect the FTSs to the STC-1000’s heat plug
2. Insert both controller’s probes into the fermentor
3. Set the STC to heat until 25C is reached
4. Set the FTSs to cool the beer to 20C.

The result: The STC-1000 will keep providing power until 25C is reached, then it will stop an hopefully save my beer.