Question

Someone claims that turning the thermostat of the central air conditioning of a warm house to the lowest level will cool the house a lot faster. Is there any truth to this claim?

Short answer

Answer: No, turning the thermostat to the lowest level does not cool the house faster. The cooling system cools the room at a constant rate, and lowering the thermostat setting only makes the system work longer, not faster.

Step-by-step solution

Understand how a thermostat works

A thermostat is a device that controls the heating or cooling system in a house or building. It does so by maintaining a set temperature by regulating the flow of warm or cool air. When the ambient temperature creeps above or falls below the set temperature, the thermostat signals the heating or cooling system to turn on until the desired temperature is achieved. Once the set temperature is reached, the system turns off.

Realize that air conditioning systems only have one speed

Contrary to popular belief, most air conditioning systems only have one speed - they are either on or off. The thermostat setting determines when the system turns on and off but not how fast it cools down the room. When the system is on, it cools the room at a constant rate.

Consider how lowering the thermostat setting affects cooling

When you turn the thermostat to a lower setting, you are setting a lower target temperature for the cooling system. The system will work harder, staying on for a longer time to achieve the new lower target. However, the rate at which the house cools remains the same because the cooling system's speed remains unchanged.

Discuss energy consumption

Setting the thermostat to the lowest level will consume more energy and keep the air conditioning system running longer. This results in higher electricity bills and potentially shorter system lifespan due to wear and tear from overuse.

Conclusion: Debunk the claim

There is no truth to the claim that turning the thermostat of the central air conditioning of a warm house to the lowest level will cool the house a lot faster. While lowering the thermostat setting may make the air conditioning system work longer, the speed at which the house cools down remains constant. Therefore, it's more efficient to set the thermostat to a comfortable temperature that is not too extreme.