Problem
The AC system stopped cooling properly after replacing the air filter.
Possible Causes
Incorrect filter size
Airflow restriction
Thermostat setting issue
System airflow imbalance
How To Fix It
Check that the new filter is the correct size
Ensure the filter is installed correctly
Check thermostat settings
Restart the HVAC system
When To Call A Professional
If cooling does not improve, a technician should inspect airflow and system performance.
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