There could be several reasons why your AC is not turning off when the set temperature is reached on the thermostat. Here are a few possible explanations:
Thermostat settings: Double-check your thermostat settings to ensure that the desired temperature and cooling mode (such as "Auto" or "Cool") are correctly set. If the thermostat is set to "On" instead of "Auto," the fan may continue to run even if the temperature has reached the set point.
Thermostat location: The thermostat's location plays a crucial role in its functionality. If it is located near a heat source (e.g., direct sunlight, electronic devices, or heat-emitting appliances), it may give a false reading and prevent the AC from turning off. Ensure that the thermostat is placed in a neutral location away from any potential heat sources.
Faulty thermostat: A malfunctioning thermostat could lead to inaccurate temperature readings and prevent the AC from shutting off when it should. Consider checking the thermostat for any signs of damage or consider replacing it if necessary.
Airflow issues: Insufficient airflow or blockages can affect the thermostat's ability to accurately sense the room temperature. Check if there are any obstructions around the vents, clean or replace air filters, and ensure that the air registers are open and unobstructed.
AC unit problems: Internal issues within the AC unit itself, such as a faulty compressor, refrigerant leaks, or malfunctioning sensors, can also prevent the system from shutting off when the desired temperature is reached. In such cases, it's recommended to contact a professional HVAC technician to diagnose and resolve the problem.
Remember, if you are unable to troubleshoot the issue or you are unsure about performing any repairs yourself, it's always best to consult a qualified HVAC technician who can assess the situation and provide appropriate solutions.