The GRIDCOOLER® Keel Cooler is mounted externally on the hull below the waterline. The engine coolant is circulated through the GRIDCOOLER Keel Cooler, which transfers heat from the coolant before it returns to the engine. The keel cooler is in constant contact with seawater to efficiently transfer heat.
A keel cooler is a closed-circuit cooling system mounted externally on the vessel’s hull below the waterline. The concept of keel cooling is similar to the application of a radiator on a car. Engine coolant is circulated through the keel cooler, which transfers heat from the coolant before it returns to the engine. The keel cooler is in constant contact with seawater allowing the cooling system to efficiently transfer heat between the coolant and seawater.
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.
The use of a keel cooler eliminates the need for seawater to enter the hull. From an environmentally friendly perspective, keel cooling provides a zero-discharge solution eliminating the possibility of contaminants entering the seawater.
We offer two types of surfaces on the interior of the copper nickel tubing Gridcooler Keel Cooler, smooth or enhanced and an aluminium Gridcooler Keel Cooler.
Copper-Nickel 90/10 – Smooth Surface
The copper-nickel – Smooth Interior Walled Tubing – GRIDCOOLER Keel Cooler is crafted using heavy walled rectangular 90/10 copper-nickel tubing. This alloy was selected based on its durability, heat exchange abilities, resistance to saltwater corrosion, and natural antifouling capabilities. Each copper-nickel keel cooler is torch brazed with 56% silver (content) braze wire to maximize the flexibility and durability of the unit.
Copper-Nickel 90/10 – Enhanced Surface
The Enhanced Interior Walled Tubing Copper-Nickel 90/10 Keel Cooler, a Fernstrum exclusive, is a truncated cone pattern on the interior of the tube generating greater heat transfer. Compared to a smooth walled tube, the enhanced tube increases the heat transfer capability by up to 30 percent. This is especially true in applications where glycol solutions are utilized. The improvement in efficiency may reduce the number or size of the units required for an application. Note: The interior surface of the tubing is determined based on your cooling requirements. Each copper-nickel keel cooler is torch brazed with 56% silver (content) braze wire to maximize the flexibility and durability of the unit.
Aluminium – 5000 Series
The aluminium GRIDCOOLER Keel Cooler is designed specifically for unpainted aluminium hull applications in fresh or cold seawater environments. 5000 series aluminium alloy was selected based on its compatibility with unpainted aluminium hulls and saltwater corrosion resistance. The alloy compatibility between the hull and keel cooler prevents pitting and avoids potential damage from interacting metals.