In a chiller, where do air and other noncondensables collect?

In a chiller system, air and other noncondensables are most likely to collect at the top section of the condenser. This is because as refrigerant cycles through the system, the vapor phase, which contains air and noncondensable gases, naturally rises to the highest point in the system due to its lower density compared to the liquid refrigerant.

In the condenser, the refrigerant is cooled and transitioned from a vapor to a liquid state. Any noncondensable gases that may be present do not condense at the same pressures and temperatures as the refrigerant, and thus they will accumulate in the upper sections of the condenser. This buildup can lead to efficiency losses and increased pressure, so it's important to monitor and manage noncondensable gases within the system.

The other options relate to components of the system where the noncondensables would not typically accumulate. For example, the bottom of the evaporator and the expansion device are not conducive environments for air and noncondensables to collect, and the compressor is designed to compress vapor refrigerant rather than collect noncondensables. Understanding this helps technicians ensure proper maintenance and operation of chiller systems.