OC: Introduction to Inspecting Heating Systems

Heat is a form of energy that is transferred from place to place according to the laws of physics. Heat always flows from a higher temperature to a lower one. Cold is the absence of heat and cannot be created; heat can only be removed. Using these basic tenets of physics, scientists and engineers have found ways to control the movement of heat so that people can be more comfortable.
During the hot summer, heat is removed from the interior of the house and transferred to the outside environment. This is called air cooling and is discussed in another unit. In the cooler months, when we want to warm a home, heat energy is removed from flame or hot electrical resistance wires and transferred, in a controlled manner, to the inside air that is circulated throughout the house. Another way to heat a home is to reverse the air cooling process and transfer existing heat energy from the outside air to indoor circulating air.
A house can be heated using appliances that are fueled by natural gas, propane, oil, electricity, solar energy, hydronic heating, steam, wood, and biomass.