Minimum heating temperature for dehydration of Cobalt Chloride
The minimum I could find is 110℃(Chemical forums) although not verified

Next is 150℃ from this link. Although, two temperature are written(110℃ and 150℃).


  mp 86 °C; loses $\ce{6 H2O}$ at 110 °C
  
  Anhydrous cobalt chloride is blue in color. It can be prepared by
  dehydration of the hexahydrate either at 150–160 °C in vacuo.


Next is 160-170℃. (Chemiday)


  $$\ce{CoCl2•6H2O -&gt;[\Delta] CoCl2 + 6H2O}$$
  The thermal decomposition of hexahydrate cobalt(II) chloride to
  produce cobalt(II) chloride and water. This reaction takes place at a
  temperature of 160-170°C in a flow dry $\ce{HCl}$.


Next is 200℃. From this paper:


  Thermal deaquation of cobalt chloride hexahydrate has been subjected
  to investigation by numerous authors because it is one of the salts
  that shows distinct steps in the loss of water of crystallization in
  the ambient temperature range  of  200℃.