Flamers only received a 25% decrease to heat generated on self.
We noted during particle optimization tests that you would overheat yourself before you overheated others depending on the asset in question.
Of course heat sinks are relative to this situation, but regardless, you shouldn't have been generating nearly as much heat on yourself as you do on others or it would be pointless to use such a weapon with a detrimental effect on one's self.
There have been no tweaks to heat generated on others, just a decrease on yourself.