ISI Technology raises $5M to bring their electric water heater to a home near you

Today, ISI Technology announced the closing of their $5 million Series A led by Wave Equity Partners. ISI is the maker of the Heatworks technology; a fully electronic water heater.

It happens every morning in households across the US: Turn the water on then check your email, brush your teeth or just wander around the bathroom for several minutes, waiting for hot water to arrive. In that time you can waste 5-10 gallons of water or more. That can really add up when you start to think about every sink and shower across the country.

The reason for this lag in heat is the technology in today’s water heaters. Cold water fills a drum where a heating element transfers energy to the water in the container and raises the temperature. More than a time-lag, existing solutions are imprecise and the heating element – which are supposed to get really hot – often breaks from constant reheating.

In 2014, ISI Technology launched the Heatworks Model1 in the Startup Battlefield at Disrupt NY. Unlike existing products, the Model1 works by taking advantage of the electrical resistance that’s inherent in the water so the only thing that gets hot inside the device is the water itself. That results in near instantaneous heating for your shower or faucet.


Since 2014, ISI has commercialized the Model1, selling several thousand units through their Kickstarter, website and Lowe’s — their primary retail partner. Founder Jerry Callahan — who previously founded Blue Rhino— said that sales are driven by a mix of individual consumers looking to retrofit their homes and multi-family or residential developers looking to save space and make new homes more efficient.

Last April, the U.S. Department of Energy, as part of the National Appliance Energy Conservation Act (NAECA), passed NAECA3 which created a host of a new, more rigorous efficiency standards for household appliances, where water heaters were the primary targets. As a result, you can no longer buy a standard size 80-gallon water heater but are limited to a 50-gallon.

As a result, ISI developed a new product, the Model1x. The Model1x is designed to connect to a 50 gal tank, now the new standard, and produce 50-100% more hot water depending on the ambient temperature.


Both the Model1 and Model1x are connected and part of the “Works With Nest” ecosystem. ISI is looking to grow distribution and expand their product line into smaller, cheaper, lighter and more reliable water heating devices. They also are exploring partnerships and licensing opportunities to get the Heatworks technology into washing machines, dishwashers and other household devices.