RSW systems

Compact and complete systems for effective refri­ge­ration of seawater and fish


The new generation of RSW systems is space-saving and based on highly efficient modern technology.

Over the past 40 years, we have delivered FrioNordica and SeaCO2ol RSW systems with refri­ge­rating capacities of 50–2 500kW to the inter­na­tional fishing fleet, the coastal shipping fleet, well boats, land-based aquaculture and the fish processing industry.

Natural refri­gerants
Our FrioNordica and SeaCO2ol RSW systems collectively provide a complete range of forward-looking solutions based on the natural refri­gerants NH3 (ammonia) and CO2. They can also be delivered with other refri­gerants. Ammonia is an ideal refri­gerant for large industrial plants, and is used exten­sively in FrioNordica RSW systems. With our smaller facilities, SeaCO2ol RSW can be offered with CO2 as the refri­gerant.


FrioNordica’s RSW plants use ammonia as their refri­gerant and are delivered in standard sizes from 350 to 2 500kW. The system has a very high perfor­mance in relation of power consumption, saves space and requires little refri­gerant charge.

Features and benefits

  • Ammonia is the most environment-friendly refri­gerant available, with excellent technical properties for large industrial RSW plants. Power consumption for an ammonia RSW is the lowest of all available refri­gerants.
  • J&E Hall rotary compressor of single screw design. Balanced compression cancels out radial forces on the main bearings. Overhaul intervals of 100 000 hours give very low mainte­nance costs.
  • Conti­nuously variable capacity control, 10–100%.
  • Variable frequency drive for compressor and pumps.
  • Seawater-cooled oil cooler for increased efficiency.
  • Titanium tubes and tube sheets in all heat exchangers. Tube joints are expanded and welded. Water heads are plastic.
  • Highly effective spray chiller with very low ammonia charge and low freeze-up risk.
  • 10-year corrosion guarantee for parts in contact with seawater.
  • FrioLogica controller offering automatic operation and monitoring of parameters. Supported and updated over the internet.
  • Heat exchangers and units are produced at our own factory in Norway.


SeaCO2ol RSW plants, which use CO2 as the refri­gerant, are built as complete and compact units delivered on a base frame. Efficient and reliable, they feature frequency regulated compressors, good part-load properties and freeze­proof RSW coolers.

The RSW plant requires little refri­gerant charge, takes little space and does not require its own room or venti­lation.

A SeaCO2ol RSW plant is delivered with seawater cooling or air cooling with outdoor gas cooler, complete with control system, compressors, valves, filters, automation and full internal cabling.

Simple and user-friendly operation via a touch­screen display, with opport­u­nities for remote control over the internet. Delivered for 3x400V, 50Hz as standard, but can also be tailored for other power supplies. Low mainte­nance costs.