Figuring out the differences between different types of air conditioners is not easy. Every type of AC is installed differently and works best with different kinds of properties.
So how do you pick the perfect AC for your home? This article covers the differences between window AC and central air in detail.
<h2> What’s the difference between window AC and central air
The difference between window AC and central air is that window AC is a temporary air conditioner installed in an open window while central air is a cooling system that distributes cool air throughout your home via ducts. Central air is generally more powerful and more efficient than a window AC.
A window air conditioner is a single unit that you install in an open window. It is designed to cool a single room or a small one-bedroom apartment.
Central air is an air conditioning system that can be fitted to cool very large buildings. The cooling mechanism is stored in one central location. The cold air it produces is then moved around your home via ducts.
The big difference is that a window air conditioner can only cool the area near the unit. A central air system can cool many rooms using a single cooling apparatus.
<h2> Cooling Capacity
Central air has a much higher cooling capacity than a window AC. A central air conditioner supplies 18,000 – 60,000 BTUs of cooling power while a window AC offers just 8,000 – 12,000.
A British Thermal Unit (BTU) is a measure of the cooling power of an air conditioner. A single BTU is the amount of thermal energy needed to change the temperature of a single kilogram of water by one degree Fahrenheit.
For reference, the 8,000 – 12,000 BTUs of cooling power offered by a window AC is enough to cool 350 – 550 square feet of indoor space. That’s about enough for a large single room or a small one-bedroom apartment.
The very smallest central air systems can beat that. An 18,000 BTU central air system can cool 700 – 1,000 square feet of indoor space, enough for an apartment with several rooms. There’s no real upper limit on central air systems, which often cool massive buildings.
<h2> Costs
Central air conditioning is much more expensive than a window AC. A window AC costs $200 – $600 while a central air system for a residential home costs $4,000 – $8,000.
That’s a pretty monumental difference. It highlights how these two air conditioning systems are really for completely different use cases.
A central air system is a permanent solution to your air conditioning problems. It works with large properties and places a premium on effectiveness and efficiency.
By contrast, a window air conditioner is designed to keep a small apartment cool. It works well as a cost-effective air conditioner for rental properties.
<h2> Energy efficiency
Central air is more efficient than window AC by a wide margin. In fact, central air is the most efficient kind of air conditioning on the market. Central air has an energy efficiency ratio (EER) of 18 – 21, much larger than the 10 – 13 typical of window AC units.
EER is a measure of how effectively an air conditioner uses its power. You can find an AC’s EEr by dividing its cooling capacity in BTUs by its power use in wattage. A higher EER means an air conditioner is more effective.
There are a few reasons why central air is more efficient than window AC. One is that a window AC is installed in an open window. As well as you can try and seal up the window AC, some heat is going to leak into your home along the sides of your window AC unit.
<h2> Should I buy a window AC or a central air?
You should buy a central air system over a window AC system if you need to keep a larger property cool. Window AC and central air systems are approaches to air conditioning designed for completely different properties.
Central air is best at catering to large properties. A high level of energy efficiency will save you money in the long run if you have a lot of room to keep cool. That’s good because central air has very high upfront costs.
A window AC is better if you’re renting an apartment. The cooling capacity of this unit is enough to keep a one-bedroom cool during the hot summer months.
The low upfront costs also mean that window ACs are viable to buy for just a couple of years if you plan to move in the future. You don’t need to modify the property to use one so there’s no need to convince your landlord to permit an installation.
Mark is a journalist who has written about home products for two years. He holds a masters degree with distinction from the London School of Economics and an undergraduate degree from the University of Edinburgh.