Window air conditioners are an affordable and efficient way to cool individual rooms, converted garages, or home offices. They’re efficient and relatively inexpensive when compared to installing central air. In some cases, they’re a quick solution to a jump in temperatures, as most hardware stores sell them.
Understanding how window air conditioners function can help homeowners make informed decisions about their cooling needs and ensure proper maintenance for optimal performance.
The Basics of Window Air Conditioners
Window air conditioners are self-contained cooling systems that cool small to medium-sized spaces. They won’t get your whole house cold but work well in a bedroom with a closed door, and if you’re renting and don’t have central air, your landlord can’t object to their installation.
A window air conditioner fits into a window, or you can mount it on the wall. These units work by extracting warm air from the room and cooling it through a refrigeration process before circulating the colder air back into the space. At less than $100 for many units, window AC units are known for their affordability and energy efficiency and are a good option for relief on a hot summer’s day.
Components of a Window Air Conditioner
Window air conditioners have several key components that work together to cool a room effectively. If you know these parts and how they work together, you can easily troubleshoot issues and maintain your unit.
Indoor Components
The indoor side of a window air conditioner, i.e., not the part that extends beyond your windowsill into the outdoors, contains several crucial parts.
The heat exchange occurs between the refrigerant and the room air in the cooling coil. The filter drier removes moisture from the refrigerant. The fan blower is a centrifugal evaporator that sends cool air back into the room. The capillary tube serves as an expansion device for the refrigerant. The drain pan collects condensate from the cooling coil.
The operation panel typically made up of buttons and up and down arrows, is where you can control the unit’s temperature and fan speed. Fancier units might also come with a remote control.
Outdoor Components
The outdoor portion of the unit houses the compressor, which compresses the refrigerant, and the condenser coil, which releases heat absorbed from the room into the outside air. The fan motor powers both the indoor blower and outdoor propeller fan and the propeller fan moves air over the condenser coil.
How Window AC Units Operate
Window air conditioners operate on a simple principle of heat exchange, sending heat out of the room and returning cooler air into the house. When you turn the unit on, the thermostat monitors the room temperature. The compressor starts once it registers that the air is too hot or above a level you’ve set.
The evaporator blower draws warm room air through the air filter and over the cooling coil. The cooling coil absorbs the air’s heat, lowering its temperature and humidity. Cooled and dehumidified air is then blown back into the room. On the outdoor side, the condenser coil releases the absorbed heat to the outside.
This cycle continues until the room reaches the desired temperature that you set on the thermostat. To prevent damage to fans and motors, most units have a built-in cooldown period of about 3 minutes before the compressor can restart. The hotter the air inside the house, the harder it is for your unit to cool the air.
Related: What is a Fan Speed Controller?
Choosing the Right Window AC Unit
Selecting the appropriate window air conditioner is crucial for efficient cooling and comfort. Homeowners should consider several factors when choosing a unit for their space.
Size Matters: BTU Ratings
The most critical factor in selecting a window AC unit is its size, measured in British Thermal Units (BTUs). Homeowners generally need about 20 BTUs per square foot of living space. Here’s a quick guide:
- 150-250 sq ft: 5,000-6,000 BTUs
- 250-350 sq ft: 7,000-8,000 BTUs
- 350-450 sq ft: 9,000-10,000 BTUs
- 450-550 sq ft: 12,000 BTUs
Choosing a unit that’s too small will result in inadequate cooling and excessive energy use as your unit works overtime to keep the room cool. Conversely, an oversized unit may cool the room quickly but fail to properly dehumidify the air, making your room clammy.
Energy Efficiency Considerations
When shopping for a window air conditioner, look for units with high Energy Efficiency Ratio (EER) ratings. The higher the EER, the more efficient the unit and the lower your electric bill. Energy Star® certified models are particularly good choices for energy-conscious homeowners who want to reduce their environmental footprint and save on utility bills.
Features to Look For in a Window A/C Unit
Modern window air conditioners have various features that enhance comfort and convenience.
Digital and remote controls allow for easy adjustments without standing up from the couch or getting out of bed. If your unit has multiple fan speeds, you can pick the airflow you prefer. With a programmable timer, you can pre-schedule a unit to turn off when you’re at work but turn on a half hour before you get home. Avoiding unnecessary use keeps utility bills low.
Some units have air filters that trap dust and allergens, improving air quality. Lastly, you can rest easy with sleep mode for nighttime energy savings. It optimizes temperature settings to save energy while sleeping.
Installation and Maintenance
Proper installation and regular maintenance ensure window air conditioners’ optimal performance and longevity. While typically priced under $100, you don’t want to replace them annually.
Installation Tips
A successful installation ensures the unit works efficiently and effectively from the start. Choose a window that can support the unit’s weight and pick one near an electrical outlet to avoid using long or extension cords, which are a trip hazard. Use weather stripping to seal gaps around the unit, preventing air leaks.
When installing the unit, put it in the window with a slight tilt toward the outside for proper drainage. If tilted inward, water can pool under the unit and rot your windowsill. Always follow the manufacturer’s instructions carefully for safety and efficiency.
Maintenance Best Practices
Regular maintenance keeps a window air conditioner in good working order. Clean or replace the air filter monthly during the cooling season to maintain airflow efficiency. A clogged filter reduces cooling effectiveness and strains the unit.
Check and clean the drain pan at least once a month. Mold and mildew can grow in standing water, so it’s clear and draining properly. While you’re at it, inspect and clean fan blades to maintain balanced airflow and efficient operation.
Annually, clean the Evaporator and Condenser Coils, as dirty coils can impede heat exchange processes. When the season is over, cover and store it away from harsh weather conditions.
Energy-Saving Tips for Window AC Users
Maximizing energy efficiency helps the environment and your wallet.
Use a programmable thermostat that will adjust temperatures automatically when you’re away or during sleeping hours to avoid unnecessary cooling. Close curtains during the hottest parts of the day to prevent additional heat gain from sunlight. Sealing air leaks around windows and doors prevents cooled air from escaping and reduces the workload on the AC unit.
To make it even easier on the unit, use ceiling fans to circulate cool air so you can set the thermostat higher on your window unit without losing comfort. Lastly, always conduct regular maintenance to keep your unit functioning at peak performance and to avoid energy waste.
Heat Pump Window Air Conditioner: A Versatile Option
Heat pump window air conditioners are a versatile solution for homeowners in climates where you’re heating your home part of the year and cooling it the other half. These units can cool in summer and heat in winter, providing year-round comfort. They also spare your back the pain of removing a window unit in the fall and carrying it down to the basement.
How Heat Pump Window ACs Differ
Heat pump window air conditioners have a reversing valve to switch between cooling and heating modes. In cooling mode, they function like standard AC units. In heating mode, the unit extracts heat from outdoor air, even when temperatures are low, and transfers it inside, effectively warming the room. This dual functionality can be more energy-efficient and cost-effective than separate heating and cooling appliances, although it will not heat below certain temperatures.
Benefits of Heat Pump Technology
Heat pump technology provides a convenient and compact air temperature control solution, offering significant energy bill savings. If you bought an older home with radiators, adding the ductwork and grates necessary for HVAC is prohibitively expensive. Heat pumps are ideal for space-limited environments where a full HVAC system may not be viable.
Innovations and Future of Window Air Conditioners
As technology advances, new features, and enhanced energy efficiency continue to transform window air conditioners. Industry innovations are leading toward smarter, more environmentally friendly solutions.
Smart Technology Integration
Many modern units now feature smart technology. Homeowners can control them remotely via smartphone apps or even voice commands through virtual assistants. This integration makes it easier to manage indoor temperatures, adjust settings, and monitor energy usage.
Environmentally Friendly Refrigerants
Manufacturers are increasingly using environmentally friendly refrigerants that have a lower impact on global warming. This shift meets regulatory requirements and aligns with sustainable practices, reducing carbon footprints and encouraging green living.
Improved Designs for Better Aesthetics
That ugly grate and white shape sticking out of your window doesn’t improve curb appeal. Manufacturers are working to develop sleeker, more compact models to fit seamlessly into modern home aesthetics without sacrificing performance. Homeowners favor these improved designs because they combine function and form.
Enhanced Noise Reduction Features
Noise is often a concern with air conditioning units. Newer models are focusing on reducing sound output without affecting the cooling efficiency. Because they use advanced materials and engineering techniques in their design, new units operate more quietly, which is crucial for small spaces and bedrooms.
Developing Trends in Energy Efficiency
The trend toward greater energy efficiency continues, with newer models showcasing higher EER ratings. Companies are working on units that deliver maximum cooling with minimal energy use, aiming to contribute positively to sustainability efforts.
Final Thoughts About Window Air Conditioners
If you’re looking for an efficient and cost-effective cooling solution during the summer, you can’t go wrong with window air conditioners. You can enjoy comfortable indoor temperatures without breaking the bank when you select the right size and maintain them properly.
As technology advances, window air conditioners continue to improve in efficiency and features that modern homeowners demand. With a little research, you can identify the best window air conditioner to keep your home cool enough for comfort without raising your electric bill.
