Understanding Heat Transfer Processes

Understanding how heat is transferred from the outdoors into your home and from your home to your body is important for understanding the challenge of keeping your house cool.

Heat is transferred to and from objects such as you and your home via three processes: conduction, radiation, and convection.

Conduction is heat traveling through a solid material. On hot days, heat is conducted into your home through the roof, walls, and windows. Heat-reflecting roofs, insulation, and energy efficient windows will help to reduce that heat conduction.

Radiation is heat traveling in the form of visible and non-visible light. Sunlight is an obvious source of heat for homes. In addition, low-wavelength, non-visible infrared radiation can carry heat directly from warm objects to cooler objects. Infrared radiation is why you can feel the heat of a hot burner element on a stovetop, even from across the room. Older windows will allow infrared radiation coming from warm objects outside to radiate into your home; shades can help to block this radiation. Newer windows have low-e coatings that block infrared radiation. Infrared radiation will also carry the heat of your walls and ceiling directly to your body.

Convection is another means for the heat from your walls and ceiling to reach you. Hot air naturally rises, carrying heat away from your walls and causing it to circulate throughout your home. As the hot air circulates past your skin (and you breathe it in), it warms you.

Thank you for reading our little science lesson. Hopefully this will help you understand more about how your heating or air conditioning units will keep you warm or cool respectively.

For more information about you heating or cooling units please contact AAA Calvert at (562) 429-1546