Shipping weight reflects calculated Dimensional Weight and is not actual product weight - see here for details.

* Sea water cooling for even higher efficiency.
* Lower power consumption.
* Silent - no fans or pumps.
* Heat removed by water means cooler boat.
* No extra holes required in hull and nothing protrudes.
* Simple to fit.
Replaces the through-hull fitting for galley sink.

The Isotherm SP unit is a totally new system that is cooled directly by the surrounding water.
This means that refrigeration efficiency is completely independent of the air temperature inside the boat.
Even on the hottest days of summer - just when a refrigerator is needed most - the sea water cooled Isotherm SP operates consistently at an extremely high level of efficiency insensitive to high ambient temperatures.
It also consumes much less battery power as no fans or pumps are required to dissipate the heat generated by the refrigeration compressor.
Although heat always rises if left to the laws of nature, the Isotherm SP unit leads the heat downwards and out through the boat's hull by utilising the natural pumping action inside the hull fitting for the galley sink drain hose. As this hose is not restricted by pumps or non-return valves, the flow inside is completely free.
Each movement of the water surrounding the boat reproduces a similar change of the water level inside the hose resulting in the pumping of a similar quantity of water in and out through the hull fitting.
By designing a special hull fitting containing a non-restricting, full-flow spiral heat exchanger for cooling the heated refrigeration agent, an extremely efficient cooling system is created.
As the hull fitting is always situated some distance from the boat's centre of gravity, even the smallest movement of the hull or mast of a sailing boat is sufficient to create a pumping action even in the calmest of waters.
This means that warm water is continuously pumped out and cold water in, movement which also prevents fouling.
The through-hull fitting is of salt-water resistant brass and the full-flow coil heat exchanger is of copper-nickel alloy.
A zinc anode comes with the kit.
The one meter long pipe connecting it to the compressor and the 3 M one from the cold-holding plate are both prefilled and fitted with quick-fit connectors.