The heat exchanger on a furnace is the section that keeps the combustion chamber and the breathing air separate. A heat exchanger is made of thin metal, and as it heats up from the combustion of the furnace, it transfers the heat to the air being distributed through the house by the blower.

While the number varies from person to person, the human body temperature usually rests around 98.6 degrees Fahrenheit. Due to your various bodily processes, your core temperature increases when you have a fever, when exposed to heat and during exercise.

While most causes of feeling hot and eye pain can be treated at home, if your toddler’s temperature is more than 102 degrees F or he exhibits other symptoms such as red or swollen eyes or a rash, consult your pediatrician immediately.

Heat stroke is a heat-related illness that occurs when a person's body temperature rapidly increases and exceeds 104 degrees Fahrenheit, according to FamilyDoctor.org, a website of the American Academy of Family Physicians.

Experiencing headache symptoms while exercising can impair the quality of your workout, which can be very frustrating while you're trying to do something good for your body. Your symptoms may indicate a minor condition that you can take steps to avoid.