Chilled Water system
A chilled water system (chiller) is a refrigeration system that cools water that is used to cool air. Chillers are used to cool large building such as hotels and stadiums. Chillers are classified as secondary refrigeration systems because the chilled water does the actual cooling of the building.
Water is cooled to about 45ºF in the chiller evaporator and pumped to the building where it cools the air.
Basic operations
- Hot air from the building is blown across coils containing the chilled water.
- Heat flows from the hot air to the cool water coils.
- This cools the air in the building and warms the water in the coil. The warm water (approximately 55ºF) is pumped back to the chiller and its heat is used to fuel the vaporization of the refrigerant in the evaporator.
- An evaporator is full of liquid refrigerant.
- The warm water from the building flows through coils in the evaporator, which are surrounded by liquid refrigerant.
- The liquid refrigerant cools down the warm water become cooled water
- The cooled water from evaporator is sent back to the building to absorb heat and cool the building air
- The liquid refrigerant vapor in the evaporator
- The vapor is rising and flow out to compressor
- The compressor compress become high-pressure hot vapor and sent to a water-cooled condenser. The heat from the vapor absorb to cooled water in the coil of condenser.
- The high-pressure hot vapor condenses become low-pressure liquid refrigerant and flows back into the evaporator
- Cooling towers is a chiller component that uses evaporation and airflow to cool water.
- A cooling tower cools water from the condenser .
- Cooling towers are usually located outside a facility.
- A fan forces air upward through the towers as warm condenser water is sprayed down.
- Some of the water evaporates as it falls, removing heat by evaporation and cooling the water left behind.
- The cool water falls to the bottom of the tower for reuse in the condenser.
- Cool water pumped to condenser and absorb heat from high-pressure refrigerant become hot water.
- Hot water flows back to cooling tower.
