Fear of heat: Thermophobia. An abnormally excessive and persistent fear of heat, including hot weather and hot objects. Sufferers from this fear experience anxiety even though they realize their fear is irrational. To avoid heat, they may live in a cold climate, wear light clothing, stay indoors on warm days, and avoid hot water and hot foods.
Thermophobia is derived from the Greek "therme" (heat) and "phobos" (fear). The opposite of thermophobia is cryophobia, fear of the cold.