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Isotherm 2051 Compact SP Water Cooled Refrigeration Component System

Isotherm 2051 Compact SP Water Cooled Refrigeration Component System

  • Maximum Box Volume (cu ft): Fridge: 4.4 or Freezer: 1.5
  • Power: 12 / 24 Volt DC, Sea Water-Cooled / Self Pumping, Max Draw: 2.5 Amp@12V
  • Small "O" Evaporator Dimensions: 9" x 3" x 8"
  • Item #: 
    Model #: 


    Shipping Weight: 
    24.10 Lbs.
    List Price: 
    Our Price:
    Note:  This item ships from the manufacturer.
    It typically ships within 2 business days  (more...)
    Status:   null Ships Direct

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    Indel Webasto Marine Product Catalog

    The Isotherm Compact Classic 2051 is a Water Cooled, Self Pumping (SP**) Refrigeration System that can cool as a refrigerator or as a freezer. The maximum freezer capacity is 1.5 Cubic Feet and the maximum refrigerator capacity is 4.4 cubic feet. This model is cooled directly by the surrounding water because it includes a Self-Pumping, Sea Water Pump that eliminates the fan and electric pump for quiet operation and offers very low power consumption.

    The SP system works without fans or water pumps to remove the heat generated by the compressor.

    The SP system consumes less battery power than a conventional seawater pump or fan cooled system (* See Specifications) and is remarkably quiet

    Sea Water Cooled (SP) Features:

    • Fridge or Freezer use
    • Sea Water-Cooled / Self Pumping
    • Patented SP System eliminates the fan and electric pump for quiet operation and very low power consumption.
    • 12/24 Volt DC Danfoss Compressor
    • Easy installation with pre-charged system, "Click-on" bracket and quick connect lines
    • See more Self Pumping Features Below

    Click Here for a Dimensional Drawing of this Product

    Click Here for a Dimensional Drawing of this Product with Ball Valve


    • Isotherm Compact SP: Type 2051
    • Maximum Box Volume: 4.4 cu ft.
      • Maximum freezer capacity: 1.5 cubic feet
      • Maximum refrigerator capacity: 4.4 cubic feet
    • Evaporator Type: Small-O
    • Dimensions evaporator: L x W x H inches 9" x 3" x 8"
    • Dimensions compressor: L x W x H inches 8" x 5" x 6"
    • Power Consumption: @ 12 Volt: 0.6 Amp Average / hour / 2.5 Amp Max*
    • Weight: 24 lb
    • Danfoss Compressor Model BD35F
    • Temp Range: Fridge

    Hull Fitting Material: The special alloy of the fitting is resistant to electrolysis and the growth of barnacles or grasses. The SP system comes complete with zinc and sea cock.

    Click Here for a Fitting Material Data Sheet for This Product

    * Note: Power consumption figures for comparison purposes are listed as the amps consumed when running / average hourly consumption on 12 volt system with 42° F in the refrigeration space, ambient air temperature 72° F. and medium sized insulation

    ** Sea Water-Cooled / Self Pumping: 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.

    Self Pumping Features:

    • Sea water cooling for even higher efficiency
    • Heat removed by water means cooler boat
    • This means that warm water is continuously pumped out and cold water in, movement which also prevents fouling.
    • Lower power consumption.
    • Silent - no fans or pumps
    • No extra holes required in hull and nothing protrudes.
    • Simple to fit
    • The included through-hull fitting is of salt-water resistant brass and the full-flow coil heat exchanger is of copper-nickel alloy
      • Replaces the through-hull fitting for galley sink
      • The one meter long pipe connecting it to the compressor and the 3 meter one from the cold-holding plate are both prefilled and fitted with quick-fit connectors.
    • A zinc anode comes with the kit

    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 utilizing 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 center 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.

    Isotherm has a 5-year limited warranty on all compressors. All other parts are covered by a two-year limited warranty with one-year warranty on labor.

    Isotherm SP Refrigeration System Replacement Zinc Anode
    Item #: 400476
  • Anode For Isotherm Self Pumping Fitting
  • Designed To Work With Isotherm SP Refrigeration Systems
  •  Include
    Model #:
    Isotherm 2351 Compact SP Water Cooled Refrigeration Component System
    Item #: 401774
  • Maximum Box Volume (cu ft): Fridge: 5.3 or Freezer: 1.8
  • Power: 12 / 24 Volt DC, Sea Water-Cooled / Self Pumping, Max Draw: 3.5 Amps
  • Medium "O" Evaporator Dimensions: 13" x 4" x 9"
  •  Include
    Model #:
    Isotherm 2050 SP Water Cooled Refrigeration Component System
    Item #: 401452
  • Maximum Box Volume (cu ft): Fridge: 4.4 or Freezer: 1.5
  • Power: 12 / 24 Volt DC, Water-Cooled, Self pumping, Max Draw: 3.5 Amps
  • Large "L" Evaporator Dimensions: 16" x 7" x 8"
  •  Include
    Model #:
    Isotherm AC / DC Voltage Converter
    Item #: 400511
  • Input: 110 Volt AC, Output: 24 Volt DC
  • Transforms AC Power into DC Power for the Compressor
  • This Unit is Not Compatible with Isotherm's Smart Energy Controller
  •  Include
    Model #:

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