I do not believe there is a parameter for this, it is not part of the controlling software, rather internal background stuff
This is not a normal error, so either the control is actually too hot or the sensor is bad. There maybe technical manuals around, I think the 2500 is really a TNC360 IIRC
call Heidenhain and see if they have any guidance.
Is the time before error predictable?
if so, see if you can pause the program at a tool change prior and shut it down for a few hours to avoid lost parts