I encountered this question the other day in a training session…
Our production facility does not use a temperature controller. Is it still important to document the coolant temperature?
In this case, it is even more important. If a temperature controller is present, then you can at least assume that the coolant temperature approximates the setpoint. If you do not have a temperature controller, then you can only guess the temperature of the water being supplied without a measurement.
If you do not have a mold temperature controller, then it is also important that you document the mold surface temperature after the mold stabilizes. When doing this, you should always provide a diagram of the actual location being measured.