Indirect Water Heater 100 Gal. 1 Coil 3/4" NPT

WiseWater Indirect Water Heaters can be used for both storing and heating domestic water. The enameled steel of the inner tank helps prevent corrosion and buildup, making it ideal for hard water regions. Our Indirect Water Heaters come with an anode rod in them to further prevent corrosion damage. They also come with polyurethane insulation, which helps to keep heat inside the tank. You can read more about the different features of this product below. We also have this particular size model available in a no-coil version. A 100gal. tank is recommended for households of 8-10 people. This product has a 1 year warranty against manufacturer's defects and is ETL listed.

Insulation Protection - CFC-free polyurethane foam insulation is injected and surrounds the inner tank, filling the space between the inner tank and outer tank. This provides an exceptionally good heat retention barrier and helps to reduce the energy cost by minimizing standby heat loss.
Electric Element - Low-density Incoloy 800 immersion type element ensures long lasting performance with choice of various heat input (kw), offering different hot water recovery rates.
Anode Protection - Each indirect water heater is provided with a magnesium anode rod to protect it against corrosion, a process well-proven in years of application.
Safety Protection - Each indirect water heater is provided with a pressure and temperature relief valve (P/T valve). It protects the indirect water heater against excessive pressure and temperature by releasing its contents safely to the floor trap via the drain pipe.

Product Information

Model 100 Gallon Number of Coils 1 Insulation Polyurethane 2"
Net Volume 103 Gallon Inlet/Outlet Size 3/4" NPT Materials
(Inner/Outer Tank)
Enameled Steel (Steel BTC340R, 0.01") / Galvanized Steel (White, 0.02")
Electric Heater 8530 Btu/hr Working Pressure 101.5psi Dimensions 68" x 29" x 29"
Wattage 2.5kW Gallon/hr Recovery 21 Gal/hr Weight 328.3lb

FAQ and Support

Sizing Guide:
For Indirect Water Heaters, it's recommended to go by number of people in the house when deciding on the gallon size. Because our water heaters come with different numbers of coils, it's important that you also consider how many coils you'll need. Here are the recommended number of people for each size and benefits/uses of the different coil models:

40gal. = 2-4 people
50gal. = 3-5 people
80gal. = 6-8 people
100gal. = 8-10 people
130gal. = 10+ people

No coil indirect water heaters, for open-loop solar/boiler thermal applications, are used for storing hot water. Instead of using a coil as a heat exchanger, a solar heater or boiler heats up the water that gets stored in the tank. (Available for 40, 50, 80, and 100 gallons)
1 coil is recommended for closed-loop solar/boiler thermal applications that have freezing or hard water conditions. The coil, a heat exchanger, has a mixture of water and food-grade glycol that passes through it to heat the water in the tank. (Available for all gallon models)
2 coils are recommended for applications that require a tank that is connected to multiple heating systems. The water heater can be used for solar hot water and solar space heating systems and also as a backup for a boiler heating system. (Available for 40, 50, and 80 gallons)

We have worked with heating systems for over 10 years and are happy to help you with any questions or concerns that you may have. You can email us at or call  833-328-6888 for help with your heating projects.