The answer to 'preventive maintenance not cooling' is that if your HVAC system is not cooling properly after regular maintenance, there could be several common causes. This could be due to issues like a refrigerant leak, a problem with the compressor, or a clogged air filter. Symptoms may include the air coming from the vents feeling warm, the system running constantly, or the home not cooling down effectively.
To troubleshoot, first check the air filter and replace it if it's dirty. You can also visually inspect the outdoor unit for any obvious damage or debris buildup. However, if the issue persists, it's best to call in a professional HVAC technician to properly diagnose and repair the problem. They have the specialized tools and expertise to identify the root cause and make any necessary repairs or adjustments to restore proper cooling performance.