From issue #6:
After buying Heat Control Operator (which name I would change to "Thermal Controller" but it's up to you) heat loss / tick value remain in the same spot (should be 0) and also when adding heat directly to reactor (via loose cell) the heat loss / tick value is changed to 1/10th of maximum heat capacity (see image below). http://i.imgur.com/fvQRf7I.png
From issue #6: