Well you’ll have to do some analysis to find out what activities and apps are causing this. There’s plenty of discussion on this above and elsewhere in the forum.
My FP4 does not heat up noticeably but as stated above and in another thread about FP4 battery performance, daily battery life has noticeably decreased since the B.048 update and doesn’t seem to have noticeably improved with the B.058 and B.065 updates we’ve had since.