In air cooled condenser, the temperature difference between the ambient air and the refrigerant in the condenser should be between _________.

In an air-cooled condenser, the temperature difference between the ambient air and the refrigerant in the condenser is known as the temperature difference or "approach temperature." It indicates how efficiently the heat is being transferred from the refrigerant to the surrounding air. The correct temperature difference range, 20 to 30°F, is optimal for most air-cooled systems because:
- Efficient Heat Transfer: A temperature difference of 20 to 30°F allows enough of a driving force for heat transfer from the refrigerant to the air, ensuring effective cooling.
- System Performance: If the temperature difference is too low (e.g., below 20°F), it could indicate insufficient airflow or inadequate condenser size, causing the system to work harder and reduce efficiency. Conversely, if the difference is too high (above 30°F), it might mean the condenser is overloaded, leading to higher refrigerant temperatures and reducing system performance.