How to tell when nozzle temperature is too high

Recently I bought some PLA filament I hadn't tried before. It seemed to flow at much lower temperatures than what I usually used, so naturally I thought I'd have no problems with clogging. However, I tried to print an Eiffel Tower file, which has hundreds of retractions, and about 2//3 the way to the top, the filament stopped feeding. Opening the extruder revealed it had broken below the hobbed bolt. Is that a sign I should try a lower nozzle temperature for this print?

usually just a sign of bad filament.
It happens.

I've got a roll of esun white filament that came with my knp - just seems to break at random points. Sometimes before a print, sometimes halfway through, sometimes while just sittign at the back of the printer.
Never had it on any other filament. Needless to say, I gave up on it fairly quickly. Just glad I hadn't paid for it :-)