Self-pumping sea-water cooled units with Mechanical Temperature Control

The mechanical thermostat represents the standard control element of the cooling unit program, being reliable and easy to use for boat owners.

Self-pumping sea-water cooled units

The Isotherm SP units cool with the use of seawater. This method has the advantage that the heat exchange is made via a water cooled condenser. The water-cooled Isotherm SP operates consistently at an extremely high level of efficiency. Without fans or pumps to remove the heat generated by the condenser, the SP system consumes less battery power and is remarkably quiet.

The Isotherm SP unit uses the movements of the hull to draw heat down and out through a special fitting in the galley sink drain hose. The flow is completely free inside the draining hose, so each movement of the surrounding water produces a similar quantity of water level inside the hose, which results in pumping an equivalent amount of water in and out. By designing a special hull fitting containing a non restricting, fullflow spiral heat exchanger for cooling the heated refrigeration agent, an extremely efficient cooling system is created.

As the hull fitting is situated away from the boat’s center of gravity, the smallest movement of the hull or mast of sailing boat is sufficient to create a pumping action. This movement results in constant withdraw of warm water and intake of cold water which also prevents fouling.

Available Product Versions

Unit code Max Volume Fridge (l)Max Volume Freezer (l)Dimensions evaporator (mm)Dimensions compressor W x H x D (mm)Weight (kg)Secop Compressor type
U100X000L11311AA100-“L“ 250 x 110 x 350280 x 160 x 17514BD35F
U125X000L11311AA125-“L“ 400 x 170 x 210280 x 160 x 17511BD35F
U125X000R11311AA125-“Oval“ 240 x 210 x 85280 x 160 x 17511BD35F
U150X000R11311AA150-“Oval“ 320 x 100 x 230280 x 160 x 17511BD35F
U000X041L13311AA-41“L“ 400 x 170 x 210280 x 160 x 17512BD35F


My Advantages

  • Fridge versions or freezer versions available
  • 12 / 24 V Secop compressor
  • Universal kit AC / DC optional for a complete power supply compatibility (12 / 24 V, 230 / 115 V and 50 / 60 Hz)
  • Easy installation thanks to “click-on” system on DC models
  • SP system (patented) to reduce the noise of a ventilated condenser and reach a lower power consumption
  • Sea water cooling for even higher efficiency
  • Lower power consumption
  • Silent – no fan nor pumps
  • Heat removed by sea water (max. temperature 28°C)
  • No extra holes in hull required
  • Simple to fit. Replaces the through-hull fitting for galley sink