Greetings! I have been looking for this device for a number of years.I saw an article about it but have not been able to find it. I am hoping t may be out there now. here is what I remember.

1.) The device had 5 heater elements within it.
2.) When the hot water is turned on all 5 elements heat up.
3.) Via a thermostatic control, each of the 5 elements will shut down as the hot water arrives, until the Hot water fully arrives, at which time te entire unit shuts down (HWT set to 120, preheater set for 115)

I see from this post, I was not the only one who had some introduction to this product. Can anyone please let me know if they have ever heard of this and where it might be acquired? Thanks!