Drain water heat recovery / Green Building & Sustainable Home Renovation Information & Advice

...heated water coming from a DWHR unit: Preheating the water heater only: The preheated water is fed into the cold water inlet of the water heater. Preheating the shower only: The preheated water is sent directly to the cold side of the shower's mixing valve. The balanced approach: The preheated water is split, feeding ...

...heated water for every gallon delivered to the shower. Maximizing efficiency with drain water heat recovery If you are worried about a smaller tank running dry, the ultimate "insurance policy" is a Drain Water Heat Recovery (DWHR) pipe. These units are vertical copper heat exchangers that replace a section of your mai...