MAREFSOL has the expertise and the means to deliver a wide range of completely assembled RSW Chiller units to the requirements of the customer.

We’ve supplied numerous Refrigerated Seawater Units, custom-designed for marine use, focussing on compactness without compromising serviceability and maintenance access. These units can come with the electrical switchboard and controls, along with insulation for the Heat Exchanger and piping.


  • Long term experience and knowhow of Natural refrigerants
  • Complete delivery and assembly of the package, incl.complete 3D design engineering by MAREFSOL BV
  • Delivery incl, P&ID, itemlists and Manuals
  • Low oil carry over due to the application of high efficiency oil separators
  • Tailor made solutions to the requirements of the Customers
  • Delivery including CE-PED declaration of conformity or certification by ships classification society

RSW Coolers

We can deliver any type of replacement RSW cooler or condenser in case of a failure due to freezing or corrosion. We will help the client to deliver a cooler that can replace the cooler on board or at site. We offer;

  • Complete design and engineering of the replacement cooler;
  • Check the thermal design of the RSW cooler with our licensed software of HTRI;
  • Check the possibility to re-use the covers of the existing RSW cooler as it will be easier to reinstall the existing piping system;
  • Check the position of original supports and connections to limit the time of reinstallation.
    classification society;

The picture besides shows a 6 Pass RSW pre-chiller cooler that can cool down 25 m3/hr of seawater from 30 to
–1 °C in one step. The cooler is a replacement cooler for a BLOKSMA cooler that failed after 10 years of operation.
The original cooler had Bronze covers which have been reused to save costs and for easier reinstallation. Delivery including CE-PED declaration of conformity or certification by any ships classification society.




Technical information

Shore and Offshore
Dimensions & Capacities
Acc. Customer requirements
Refrigeration data
Ammonia, HFC’s, CO2 , Propylene, R404a, R507, R449a, etc.
Design temperatures
From -50 °C and higher
Design Pressure
Up to 100 Bar
Oil carry over
Unit design
Solidworks Premium
Thermal design
MAREFSOL (HTRI software)
Unit design / Arrangement
Mechanical design
Refrigeration design
Heat Exchanger materials
Carbon Steel Titanium CuNi 90/10 CuNi 70/30 Stainless; AISI 304, 316L, 316Ti Super duplex; SAF2205, SAF2507
Covered standards, design codes and Classification soci-eties for unit design
Standards and design codes CE-PED ASME (U-stamp) BS-PD5500 AD Merkblätter
Stop valves
AWP or Danfoss
Control equipment
Electric motors
Siemens, Leroy Somer, WEG