Bundled to perfection

Boxcoolers are efficient cooling systems designed for installation in most inland and sea-going marine applications. Boxcoolers cooling the primary circuit using seawater. A closed-circuit cooling system, which do not need any water-filters, valves, inboard heat exchanger, raw water pumps, seawater piping and strainers. The boxcoolers can be mounted longitudinal or transversal in the sea chest.


Engineered to cool

The heat source cooling water is circulated through the boxcooler tube bundle, which is suspended in the sea chest. Heat is transferred from the boxcooler tubes to the seawater, causing it to rise due to its lower density creating a natural upward circulation.

Openings in the bottom and upper side of the sea chest help to direct and focus the natural convection flow of seawater through the sea chest and across the boxcooler tubes. Additional cooling efficiency can be realized through forced circulation induced by the motion of the vessel.


Compared to an open circuit cooling system (inboard heat exchanger), a closed-circuit cooling system provides several distinct advantages. A closed-circuit cooling system eliminates the need for an inboard heat exchanger, raw water pumps, strainers, seawater piping, and the high maintenance associated with open circuit cooling systems. It also eliminates silt and sand build-up in the cooling circuit and protects the system from saltwater corrosion.

From an environmentally friendly perspective, our WME Program (including our Weka Cu/Ni 90/10 Boxcooler and circular economy service) provides a zero-discharge solution eliminating the possibility of contaminants entering the seawater.


Strong and solid cooling solution

The WEKA Boxcooler® is a custom engineered cooling solution designed to meet the specific demands of the engine manufacturer and operating conditions of your vessel. This design is ideally suited for vessels operating in icy, sandy, or debris laden water.

Marine Applications

  • Barges

  • Cargo Ships

  • Carriers

  • Dredgers

  • Ferries

  • Fishing Vessels

  • Ice Breakers

  • Supply Vessels

  • Tankers

  • Tugs

Heat sources

  • Air Conditioning Units

  • Bow Thrusters

  • Compressors

  • Electrical Equipment

  • Generator Sets

  • Hydraulics

  • Propulsion & Auxiliary Engines

  • Pumps

  • Reduction Gears

Copper-Nickel 90/10

The copper-nickel Weka Boxcooler is crafted using 90/10 copper-nickel tubing. This alloy was selected based on its durability, heat exchange abilities, resistance to saltwater corrosion, and natural antifouling capabilities.


The Selection of possible materials

The Weka Boxcooler is a completely assembled unit and is factory tested to ensure dependability. Depending on your application and situation the Weka sales and engineering team will assist you in selecting your material for your situation.

Aluminium Brass

The aluminium brass boxcoolers are used throughout the marine market and is mainly used for its strength. Nonetheless this alloy needs a protective coating and protection system due to its inherent corrosion resistance to seawater and lack of natural anti-fouling capabilities.


In some situations, a treatment of boxcoolers with phenol heat-cured coatings is necessary. This is important for the protection against galvanic corrosion and combines this with high heat-conductivity properties.

Natural Anti-Fouling

This image illustrates a comparison between traditional aluminum brass tubes with hard baked coating (left side) and uncoated 90/10 copper-nickel tubes (right side). It’s the result of a six weeks feasibility test. The high copper content of the tubing provides natural anti-fouling capabilities, offering protection against marine growth. Copper alloys possess an inherent natural resistance to biofouling. Clearly, the 90/10 Cu-Ni alloy is resisting fouling from algae mussels and other marine growth. For clarification, the biofouling resistance of copper alloys is due to the copper in the protective oxide film; it is not from the leaching of copper ions.

Eliminates raw water pumps, strainers, and filters
Virtually maintenance free
Cools engines up to 40,000 kw
In-hull protection

Copper-Nickel 90/10 Advantages

Amazing results after a 6 week feasibility study

Bottom mounted

In a bottom mount application, a special top sea chest plate is pre-manufactured and secured to the unit’s mounting frame.

Aftward or longitudinal

Boxcoolers can be installed in an aft ward or longitudinal position, depending on the design of the vessel or application.

Top mounted installation

In most cases, a Boxcooler is installed in a top down fashion by lowering the unit into the mounted frame and welding the unit to the top of the sea chest.

Weka Protector & Guard

This equipment helps to minimize potential damage to the units and hull from stray electrical currents and galvanic corrosion.

Installation & design options

Depending on your operating conditions and hull design.

Single or multiple

heat sources

A Boxcooler can be designed to support single or multiple heat sources on one unit. One Circuit cools a single heat source. A Boxcooler with multiple circuits can cool more than one heat source.

Stepped Boxcooler

A Boxcooler can be engineered to accommodate tight spaces by stepping the unit. Our engineering department will assist you in designing the best possible cooling solution.

Sea Chest Design

The sea chest requires careful planning. The inlet and outlet slots of the sea chest must provide a constant flow of seawater over the boxcoolers tubes. The outlet slots must always remain below the waterline, even when the vessel is in a light draft condition.


Upon request the Boxcoolers can be supplied with a test certificate of one of the well-known classification societies. For example, ABS, Bureau Veritas, DNV-GL, Lloyds Register of Shipping, RINA, RMRS, RRR and various others upon request.