What type of air does the blower in each cockpit evaporator module pull through the evaporator coils?

The blower in each cockpit evaporator module pulls through the evaporator coils ambient cockpit air. This is critical as it allows the system to effectively cool and dehumidify the air that is within the cockpit. By drawing in ambient cockpit air, the evaporator coils can remove heat and moisture from this air, leading to a more comfortable environment for both the pilots and passengers.

Using ambient air specifically helps maintain appropriate temperatures and humidity levels, which is essential in the confined space of an aircraft cockpit. If recycled cabin air were used, it might be less effective in cooling because the air would already be warmer and potentially more humid. Therefore, the decision to utilize ambient cockpit air ensures that the system can operate efficiently and maintain optimal conditions.