About Fernstrum

R.W. Fernstrum & Company has been engineering and manufacturing GRIDCOOLER Keel Coolers for the marine industry since 1949. Fernstrum® has since partnered with WEKA Marine to expand our product offerings. Our products are used for cooling marine propulsion engines, generator sets, reduction gears, and auxiliary systems onboard vessels of all sizes worldwide. Each solution is engineered to meet the requirements of your engine, vessel, and operating conditions.

Contact our sales and engineering team for expert advice on cooler sizing, placement, installation, and service.

R.W. Fernstrum & Company is an ISO 9001:2015 Certified Company. 

Our Heritage

R.W. Fernstrum & Company, a global leader in engineering and manufacturing keel cooling technologies, was founded in 1945 when our founder Robert W. Fernstrum patented the first rectangular tube keel cooler with an angled header for the United States Army and Navy. During World War II, the U.S. Navy encountered engine cooling problems with their landing craft and required a new closed-circuit cooling system. At the time, Mr. Fernstrum was working with Gray Marine, the engine manufacturer powering the landing craft. The Navy approached Gray Marine regarding the problem and tasked Robert with the responsibility of creating a closed circuit cooling system. After intense research, Mr. Fernstrum developed the basic keel cooler design that is used today.

The GRIDCOOLER Keel Cooler has evolved over the years into a line of keel coolers that offers nearly limitless variations to fit a particular application. Our commitment to bringing the latest in cooling technologies to the marine industry, has earned more keel cooling related patents than any other company. Our devotion has built a respected reputation for outstanding quality and service throughout the marine industry.

Fernstrum’s product offerings has grown through strategic partnerships. In 1997 R.W. Fernstrum & Company partnered with WEKA Marine B.V., a Dutch company, to manufacture and sell copper-nickel boxcoolers for North and South America. The WEKA Boxcooler® is a compact, closed circuit cooling system that is mounted within the confines of the ship’s hull.

Over the years, R.W. Fernstrum & Company has grown into a worldwide organization with 24 representatives across 6 continents. Focusing exclusively on marine cooling, this third-generation, family-owned business has built a respected reputation throughout the industry for exceptional quality and service. The Fernstrum sales and engineering team will provide you with expert advice on cooler sizing, placement, installation, and service.