If you set your air conditioner to 60 degrees Fahrenheit (or approximately 15.6 degrees Celsius) when it's 30 degrees Fahrenheit (or approximately -1.1 degrees Celsius) outside, the air conditioner will attempt to cool the indoor air to the set temperature regardless of the outdoor conditions. However, the outcome will depend on the capability of the air conditioner and the specific conditions in your home.
Cooling Capability: Air conditioners are designed to cool the indoor air to the desired set temperature, but they have limitations in terms of their cooling capacity. If the outdoor temperature is much higher than the set indoor temperature, the air conditioner may struggle to reach 60 degrees Fahrenheit, especially if it's not powerful enough for the size of the room or if there are air leaks that let warm air into the space.
Efficiency and Energy Consumption: Running an air conditioner at a very low temperature, such as 60 degrees Fahrenheit, when it's cold outside can lead to inefficiencies and increased energy consumption. Air conditioners are generally more efficient when operating at moderate temperatures. Cooling the indoor air to such a low temperature while it's already cold outside may lead to excessive energy use and higher electricity bills.
Compressor Stress: The air conditioner's compressor, responsible for cooling the air, might be put under additional stress if it needs to work constantly to achieve and maintain such a low indoor temperature. This could potentially lead to increased wear and tear on the system and reduce its overall lifespan.
Uncomfortable Indoor Conditions: Setting the air conditioner to such a low temperature when it's already cold outside could make the indoor environment uncomfortably chilly for occupants. It's generally more comfortable to set the air conditioner to a temperature closer to the outdoor temperature, allowing for a gradual cooling effect.
To optimize comfort, energy efficiency, and the lifespan of your air conditioning system, it's best to set the indoor temperature to a reasonable level, such as 68-72 degrees Fahrenheit (20-22 degrees Celsius), regardless of the outdoor temperature. This will provide a comfortable indoor environment without putting unnecessary strain on the air conditioner and your energy bills. Additionally, consider using a programmable thermostat to adjust the temperature based on your schedule and preferences throughout the day.