Keel Cooling

Hello …and thanks for some very interesting articles through many years.
At you site I found: “with its Danfoss DB50 compressors, evaporator plates, and keel cooler (inside a fresh water tank welded to the hull) works very well”.
We have to upgrade the fridge/freezer in our aluminum sailboat and would like to copy the internal cooling you mentioned.
Wondered if you would care to share some more detail on the design of the tank, and maybe a comment on possible corrosion problems?

Regards Carsten Hvingel

Hi Carsten:

Re corrosion, the bronze keel cooler is bolted through a fiberglass tank lid – you need some form of isolation in whatever you do. Tank liquid is deionized water with antifreeze added to the required temperature. Note that if you do not need cold weather protection leaving the antifreeze out is more efficient.

A tank of about 20 gallons/80 liters is sufficient to handle our freezers and fridge with the boat hauled out. Shape should favor surface area over depth, but in the end depends on your structural system and space between framing.

Good luck.

Posted by Steve Dashew  (December 18, 2010)

One Response to “Keel Cooling”

  1. Air Conditioning Rental Says:


    A keel cooler is a closed circuit cooling unit mounted on a vessel’s hull beneath the waterline.