HWL - Hot water loop

The Alfa Laval Hot Water Loop is a steam heated system that delivers heat to equipment in marine applications. It ensures a constant temperature and can be used anywhere hot water is needed, e.g. constant hot water supply for fresh water generation or diesel engine pre heating.

hot water loop

HWL benefits

  • More customized module options, 3 scopes of supply, result in free space for other equipment and lower CAPEX possibility.
  • Lower electrical power consumption, 0.5-12 kW, thanks to bypass pipe on hot water pump.
  • More uptime thanks to automatic operation.
  • Thanks to simple operation there will be less time for start-up due to no manual adjustment for finding mixing temperature.


  • Modular, compact design
  • Flexibility in operation
  • Automatic operation
  • Prepared for pre-heating of the main engine or other equipment


Kako deluje

The water in the Hot Water Loop is heated by means of steam. The amount of steam is regulated by a steam control valve, based on the set point of a temperature controller mounted in the hot water outlet line. A hot water pump ensures a constant flow to the Hot Water Loop heat exchanger, and makes recirculation possible when the engine is at low load or stopped. This pump must be running when the Hot Water Loop is used for engine preheating. A blinded flange connection makes it possible to connect the Hot Water Loop for various heating or preheating purposes.

hot water loop