If an air conditioner has been off for a long time and fails to cool when turned on again, there are a few possible reasons for this issue. While it's best to have a professional examine and repair the AC, there are a few steps you can take before calling for immediate assistance:
Check the Thermostat Settings: Ensure that the thermostat is set to the cooling mode and the temperature is set lower than the room temperature. Sometimes, the settings may have been adjusted accidentally or changed during the time the AC was turned off.
Clean or Replace the Air Filter: A dirty or clogged air filter can restrict airflow and hinder the AC's cooling performance. Check the air filter and clean it if it's dirty. If it's heavily soiled or damaged, consider replacing it with a new one.
Inspect the Condenser Unit: The condenser unit, typically located outside the building, may have accumulated dirt, leaves, or debris during the period the AC was off. Inspect the condenser and ensure it is clean and free from obstructions. Gently clean the unit if necessary.
Allow Time for Cooling: If the AC has been off for an extended period, it may take some time for the system to cool the space. Give it sufficient time to operate and see if the cooling improves gradually.
Verify Power Supply and Circuit Breakers: Ensure that the AC unit is receiving power by checking the electrical connections and verifying that the circuit breakers or fuses are not tripped or blown.
If these steps do not resolve the issue and the AC still does not cool properly, it is recommended to contact a professional HVAC technician. They have the expertise and tools to diagnose and address more complex problems with the AC system, such as refrigerant leaks, faulty components, or compressor issues. It's important to address AC problems promptly to avoid further damage or inefficiency.