Central low temperature cooling water system

The central purpose of the low-temperature cooling water system is to cool the service units and the excess heat dissipated from them, together with the excess heat collected by the HT cooling system to transfer the overboard water to the main cooling system.
The closed-circuit low-temperature (LT) central freshwater cooling system is equipped with circulating water pumps (in the case of three, three pumps) that supply water through two central water-cooled central coolers to the cooled equipment or its coolers. In addition, low-temperature freshwater supply pumps may be installed to improve the cooling water supply (two pumps in the example) or low-temperature freshwater supply pumps for a specific installation (in the case of an inert gas generator freshwater cooling pump in the example).
When the overboard water temperature is low, one Central Cooler is used for cooling, the other is in standby mode. When the overboard water temperature is high or there is a high need for cooling, both coolers will be needed.
During normal operation of the LT cooling system, when the overboard water temperature is low, one circulation pump will operate. The other two circulation pumps will be in standby mode. At overboard water temperatures high, two circulation pumps will be required.
Low temperature fresh water pumps pump from low and high temperature systems and discharge water directly to central coolers.
The thermostatically controlled three-way valve regulates the flow of water to the cooler (s) so that the temperature of the circulating fresh water is maintained.
The fresh water expansion tank (in the HT cooling system in the case of the sample) ensures a proper static pressure in the cooling systems (in both cases in the example) and also compensates for the thermal fluctuations of the water volume.
The system may provide (for example, two) blindfolded connections that are used to connect directly to an external cooling system when the ship is in a dry dock or other similar condition.

Example of a central low temperature cooling water system