Sometimes the water chiller may out of work, but you want to try to fix it by yourself. At this moment, it is very important that know the components of the water chiller. Next, this passage will introduce you the components of the water chiller.
The evaporator, or cooler, as it is often called, is the vessel in which the water is cooled. There are several designs of evaporator, and their use is typically based on the size of the chillers.
For smaller capacity chillers (15-60 tons), the brazed-plate evaporator is often used. These evaporators consist of a series of plates brazed together with every second plate turned 180 degrees. This design creates two highly turbulent fluid channels that flow in opposite directions that result in a high heat transfer coefficient over a small surface area. The plates are stacked so they form a multilayered design for two independent paths of fluid to travel. Each layer or path is linked to an inletandoutlet via a manifold at either end.
The direct expansion (DX) evap-orator is a shell-and-tube heat ex-changer design in which the refrigerant flows through the tube sand the water flows around the tube inside the shell section. As heat is transferred to the colder refrigerant from the warmer water, the refrigerant in the tubes boils while the water is cooled. Baffles within the shell direct the water flow path over the tubes to create turbulence,resulting in improved heat transfer.
In larger capacity water chillers, the cooler is normally a shell-and-tube heat exchanger with the refrigerant on the shell side and the heat transfer fluid passing through the tubes. This fluid can be fresh water,an antifreeze mixture, or any process liquid that requires cooling. The advantage to this type of heat exchanger is that the tubes can be mechanically cleaned. The fluid in a chilled water loop is chemically treated and closed to the environment to protect the equipment and piping system from corrosion and fouling.
Parallel and Series Chiller Evaporators
Where chiller capacities greater than can be supplied by a single chiller are required, or where standby capability is desired, chillers may be installed in parallel. Units may be of the same or different sizes, a properly size of water chiller is important. Usually, equally sized chillers are utilized to accomplish commonality of parts and maintain simplicity. If unequal sized chillers are used, cooler flow rates must be balanced to ensure proper flow to each chiller.