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Isotemp Basic 75 Marine Water Heater - 20 Gallon

Isotemp Basic 75 Marine Water Heater - 20 Gallon

  • Capacity: 20 Gal., Orientation: Horizontal or Vertical, Heat Exchanger: Front
  • Select Voltage / 750 Watts, Tank Material: Stainless Steel
  • Dimensions: 42.2" L x 15.5" OD, Exterior: Stainless Steel
  • Item #: 
    Model #: 
    Multiple Models Available
    Shipping Weight: 
    80.00 Lbs.
    Reg. Price:
    Sale Price:
    Please enter quantity below.

    Model #
    115 Volt AC
      *In Stock!*
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    Reg. Price: $929.99
    Sale Price: $836.99
    230 Volt AC
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    Reg. Price: $929.99
    Sale Price: $836.99
    Click the "More Info" button above for specific information about that product.

    Shipping Note:
    It ships ONLY by Truck Freight.
    Please call us at 800-628-8225 or E-mail for a valid shipping quote, since Truck Freight rates change regularly.
    This item ships directly from the manufacturer.

    Indel Webasto Marine Product Catalog

    Available Models:

    Model: 607521B000003 - Power: 115 Volt AC
    Model: 607531B000003 - Power: 230 Volt AC

    Isotemp Water Heaters General Features:

    • All Isotemp water heaters use two thermostats: a temperature thermostat and a safety thermostat designed to trip in the event the tank is run dry
    • All Isotemp water heaters come standard with a mixing valve
      • Every Isotemp tank features a safety mixing valve that regulates the temperature of the water coming out of the tank so that water heated to 160+ degrees will not scald boat owners or their guests
      • Temperature of the hot water coming out of the tank can be adjusted to the preference of the owner by turning the mixing valve on the water heater
      • This feature allows the thermostat to be set at a higher temperature, while keeping the user safe from scalding
      • It also extends the capacity of onboard hot water by using only a fraction of the water in the tank to produce the desired water temperature
    • Standard heating elements are 750 watts which won’t overload generators or trip dock breakers
    • All Isotemp products are CE certified and manufactured in ISO certified facilities
    • All Isotemp tanks are covered by a 5-year limited warranty against leakage due to manufacturing defect or corrosion and a 2-year warranty on all other parts
    • 750 Watt immersion heating element as standard on all Isotemp Water Heaters
      • 1200 Watt and 2000 Watt Elements are available as an option (Special Order Only)
        • Note: 2000 Watt heating element is only compatible on 230 Volt versions

    Isotemp Basic 75 Marine Water Heater Features:

    • Specifically designed for use on yachts and boats, and built with highest quality components to ensure long service life in the marine environment
    • Aluminum mounting brackets adjustable 360° for horizontal (deck) or bulkhead (vertical) installations
    • Engine water heat exchanger and immersion heating element positioned at bottom of tank to ensure consistent heating of all water in tank
    • Extra-long, corrugated coils for high heat exchanger efficiency
    • Water inlets and outlets specially designed to minimize mixing of cold and hot water
    • Thermostatic mixing valve conserves hot water, protects against accidental scalding and minimizes power consumption
    • Special 7.0 bar / 100 PSI safety valve makes winterization easy
    • Internal tank, engine water coil and fittings made of AISI 316 stainless steel
    • External jacket / tank and mounting feet made of non-magnetic AISI 304 stainless steel
    • Ultra-thick polyurethane insulation minimizes heat loss
    • 2-year full warranty, 5-year limited warranty on inner tank against corrosion and material stress


    Part No.
    Tank Capacity
    20 Gallon
    20 Gallon
    Power (Heating Element)
    115 Volt AC / 750 Watts
    230 Volt AC / 750 Watts
    Rated Pressure (bar)
    Horizontal or Vertical
    Horizontal or Vertical
    Heat Exchanger
    Inlet / Outlet Ports
    Male 1/2" NPT
    Male 1/2" NPT
    Safety Mixing Valve
    Pressure Release Valve

    Isotemp has a 5-year limited warranty on the Isotemp water heater tank. All other parts are covered by a two-year limited warranty with one-year warranty on labor.

    Documentation available at the following links:

    Sea Tech Water System Tubing - 1/2 Inch
    Item #: 501303
  • Diameter: 1/2" ID, Select Color
  • Material: Polyethylene, Tolerance: 180° F @ 100 PSI / 72° F @ 160 PSI
  • Sold by the Foot, ( 50 feet Maximum Continuous Length )
  •   null
    Model #:
    Multiple Models Available
    Isotemp Basic 40 TCT Marine Water Heater - 11 Gallon
    Item #: 502691
  • Capacity: 11 Gal., Orientation: Horizontal or Vertical, Heat Exchanger: Front
  • Select Voltage / 750 Watts, Tank Material: Stainless Steel, Dual Exchanger
  • Dimensions: 25" L x 16" OD, Exterior: Stainless Steel
  •   null
    Reg. Price:
    From: $887.99
    To: $909.99

    Sale Price:
    From: $799.19
    To: $818.99

    Model #:
    Multiple Voltage Choices Available

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