Leaving a window open while running an air conditioner can potentially strain the AC system and reduce its efficiency, but it is unlikely to "break" the air conditioner directly. However, there are some important considerations to keep in mind:
Reduced Cooling Efficiency: When you leave a window open while the air conditioner is running, warm air from outside will enter the room. This makes it harder for the air conditioner to maintain the desired temperature, as it needs to continuously cool down the incoming warm air. As a result, the AC may run longer and work harder to achieve the set temperature, leading to increased energy consumption and higher utility bills.
Humidity Concerns: Depending on the climate and humidity levels outside, leaving the window open might introduce excess humidity into the room. High humidity can make the indoor environment feel uncomfortable and can strain the air conditioner, as it needs to remove not only the heat but also the added moisture.
Risk of Overworking the AC: If the temperature outside is significantly higher than the desired indoor temperature, the air conditioner may have to work continuously without achieving the desired cooling effect. This prolonged operation can put extra stress on the AC unit and potentially lead to premature wear and tear.
Dust and Allergen Infiltration: An open window can allow dust, pollen, and other allergens to enter the room. These particles can accumulate on the AC's filters and coils, reducing its efficiency and affecting indoor air quality.
Security Concerns: Leaving a window open might compromise the security of your home, allowing easier access for intruders or pests.
While leaving a window open is unlikely to directly break the air conditioner, it can lead to increased wear and tear, reduced efficiency, and potentially higher maintenance costs. To maximize your air conditioner's performance and energy efficiency, it is generally best to keep windows and doors closed when the AC is in operation. If you want to let in fresh air, consider turning off the air conditioner temporarily or using a window fan to create cross-ventilation when outdoor temperatures are mild.