The difference between 72 degrees on a heater (furnace) and an air conditioner lies in the context of their operation and the purpose they serve:
Heater (Furnace) Set to 72 Degrees: When you set a heater (furnace) to 72 degrees, it means you want to maintain a comfortable indoor temperature of 72 degrees Fahrenheit (22 degrees Celsius). The heater's job is to warm the indoor air to reach and maintain the desired temperature. The heater achieves this by generating heat, usually through combustion (in the case of gas furnaces) or electric resistance heating elements (in the case of electric furnaces).
Air Conditioner (AC) Set to 72 Degrees: When you set an air conditioner to 72 degrees, it means you want to maintain a comfortable indoor temperature of 72 degrees Fahrenheit (22 degrees Celsius) by cooling the indoor air. The air conditioner's primary function is to remove heat from the indoor air, effectively lowering the temperature to the set value. It achieves this through a refrigeration cycle that absorbs heat from the indoor air and releases it outside, leaving the indoor environment cooler.
In summary, the main difference between 72 degrees on a heater and an air conditioner is the direction of heat transfer:
Heater at 72 degrees adds heat to the indoor air to reach and maintain the desired temperature.
Air Conditioner at 72 degrees removes heat from the indoor air to reach and maintain the desired temperature.
Both systems play a vital role in maintaining indoor comfort, with the heater being used in colder months to provide warmth, and the air conditioner used during warmer months to cool the indoor environment. The specific temperature setting of 72 degrees is a matter of personal preference and comfort, and individuals may choose different temperature settings based on their thermal comfort and energy efficiency preferences.