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Isotemp
Isotemp SPA 20L Marine Water Heater
Item: #870739 | Part Number: Not Selected$652.80 - $683.20
Description
The Isotemp SPA 20L Marine Water Heater delivers reliable onboard hot water with a compact 20-liter (5.3 gallon) capacity and rugged marine construction. Featuring a stainless steel tank, dual thermostats, and a safety mixing valve, it provides safe, adjustable water temperatures while minimizing heat loss. Designed for long service life, it's ideal for marine showers and galley use.
Isotemp SPA 20L Marine Water Heater Item # 870739
Description
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 750W which won't overload generators or trip dock breakers
- All Isotemp products are CE certified and manufactured in ISO certified facilities
- 750W immersion heating element as standard on all Isotemp Water Heaters
- 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
Isotemp SPA 20 Marine Water Heater Features:
- Exterior casing / jacket made of high quality polypropylene
- Inner tank made of AISI 316 stainless steel
- Includes safety valve, mixing valve and plug
- Robust design and manufactured to highest-quality marine standards for long service life
- Immersion heating element specially designed to heat water at bottom of tank
- Thermostat-controlled mixing valve standard on all Isotemp water heaters
- Aluminum mounting brackets adjustable for deck or bulkhead installations
- Extra-thick insulation for low temperature loss, high performance
- Extra-long corrugated coils for high heat exchange efficiency
- Five-year limited warranty on inner tank against corrosion and material stress
Specifications:
- Tank Capacity: 5.3 Gal
- Rated Pressure (bar): 6.0
- Orientation: Horizontal or Vertical
- Heat Exchanger: Front
- Inlet/Outlet Ports: Male 1/2" NPT
- Includes Safety valve and Mixing valve
- 115V AC Model (6P2023SPA0003):
- Power (Heating Element): 115V AC/750W
- Plug: USA
- 230V AC Model (6P2031SPA0003):
- Power (Heating Element): 230V AC/750W
- Plug: European
Part Numbers for Isotemp SPA 20L Marine Water Heater
Reviews
Rated 4 out of
5
by
Cedarman from
Caution - Oddball fittings
Nice unit but had a difficult time with fittings. The engine coolant loop fittings and the cold water inlet are standard 1/2" MNPT fittings but the hot water outlet is a 1/2" BSPP (British Standard Pipe Parallel) fitting, also known as G-thread or G-1/2. It's a parallel thread that uses a washer to seal. These fittings are most commonly found in the US on shower heads/hoses. The inconsistency is stupid! I had to purchase a BSPP to MNPT adapter from Amazon to make it work.
Date published: 2025-11-04
Rated 5 out of
5
by
Captain Dan from
Great little water heater!
This heater is awesome! I love the low wattage element for low wattage marina supply or a generator feed, and the high temperature set point AND the adjustable mixing valves so you don’t burn yourself! A home run combination!
The adjustable stainless steel mounting bracket makes the install much easier than a fixed one. Do yourself a favor and get one of these heaters today!
Date published: 2025-06-28
Questions
What are the dimensions of the unit
The dimensions are on the image and are listed for the 15. 20 and 25 units.
https://defender.com/media/catalog/product/cache/a2bf45e9635ff86c8c09fbc84b193941/catalogimages/isotemp/spa-20-marine-water-heater-6p2023spa0003--1.jpg
Date published: 2024-03-26