Possible reasons and solutions for poor air cooler performance:
1. Low cooling water pressure --- increase the water pressure.
2. The cooling water pipe is clogged with foreign objects - clean and clean it.
3. The cooling water temperature is high: this is the most common problem in summer. You may consider using deep well water.
4. The air cooling chamber has a poor seal --- leak.
In addition, you can observe the temperature difference between inlet and outlet water and analyze the cooling effect of the chiller. If the efficiency has reached the standard, it is not a design problem.