How it Works
Breaking the laws of physics.
Eternal Hybrid™ and Eternal Condensing Hybrids work on the Counter Flow Principle. This is an opposite approach to the way industry has traditionally built water heating appliances. Unlike any other water heater appliance, Eternal has achieved the highest efficiency in the industry without sacrificing your comfort.
The Old Way
Tank
In a tank, heat is generated from the bottom of the tank and rises through the centrally mounted exhaust. Cold water enters from the top and deposits sediments at the bottom.
Over time, the efficiency of heat transfer is reduced as the burner has to work through the build-up before heating the water.
As heat passes through a large body of water just once, the tank is limited in its ability to produce continuous hot water.
Tankless
In a tankless, heat is also generated in a bottom up fashion. Cold water passes through series of coils that reduce water pressure in order to heat water quickly. However, the coils clog up over time with scale build-up that reduces efficiency, and eventually causes the heat exchanger to fail.
Because tankless is activated by flow alone, every time a faucet is opened and closed the heating cycle must start over again. This on/off behavior causes "cold water sandwich" that impacts temperature consistency as well as delay hot water delivery to your applications.
The Hybrid Way

Eternal
In Eternal's Counter Flow design, cold water enters from the bottom up as a way of self cleaning the sedimentation, while heat is pushed through 44 radiating transfer pipes.
Eternal Condensing Hybrid engineered an unprecedented 3 cycle process by pushing heat in 3 directions through the water and maximized energy transfer. In simplest terms, our patent slows the exhaust of heat by reusing the energy multiple times, rather than reducing water pressure.
The end result is a small heat exchanger that is capable of replacing multiple tanks, while supplying endless hot water with consistent water pressure and doing it efficiently time after time.
Join us at our test bench as we compare the Eternal Condensing Hybrid with a competing name brand Condensing Tankless and see the difference. Watch the video!
Want to see what actual customers think of their Eternal Hybrid™? Read our most recent reviews posted by owners and check out our testimonials section.
The original Eternal Hybrid™ shook up the industry in 2006. It even caught the attention of Extreme Makeover: Home Edition designer Ed Sanders.