Hot Water Energy Recovery 1 Endorsement

Drain water heat recovery systems capture energy from hot graywater and use it to partially preheat supply water, significantly reducing energy use with no moving parts.

Top Provider Rodell Architects

Drain water heat recovery systems — also known as drainline or gravity film heat exchangers — capture energy from graywater and use it to preheat supply water. Typically installed in the basement as part of the drainage stack, the systems lead to either a hot water tank or to an appliance that concurrently uses hot water and produces warm wastewater, such as a shower. or dishwasher, since this presents the best opportunity to increase efficiency. Bathtubs and washing machines, on the other hand, aren’t effective applications for this type of technology given that they are filled once and then drained.

In a Drain Water Heat Recovery (DWHR) application, falling drain water forms a thin film that rapidly imparts its heat to the colder pipe wall. The Power-Pipe® captures much of this heat, then "recycles" it to raise the temperature of incoming cold water. A 60-inch Power-Pipe System, for example, can raise the cold water temperature from 10°C (50°F) to as much as 24°C (75°F), under equal flow conditions. Because the incoming cold water is preheated before going into the water heater and plumbing fixtures, the water heater uses less energy to raise the temperature of the water to the desired level for use, which saves money and increases the effective water heater capacity.

With an easy installation by any plumber, ZYPHO® offers shower drain heat recovery systems leading to energy savings and reducing carbon footprint, without compromising the aesthetics of your space.

ZYPHO transfers heat from the shower’s wastewater (40ºC) to the incoming cold mains (10ºC) supply. This preheated water (up to 31ºC) is then directed to either the shower mixer, the water heater or, preferably both - reducing energy consumption from 30% to 67% - Improving Energy Efficiency. Every three showers, two are for free.

To obtain correct shower water temperature, hot and cold water are combined at the shower mixer tap. Both have different origins: hot water comes from a heating device, for example from your electric or gas water heater, and cold water comes directly from the mains. Depending on the temperatures of cold mains and hot water, you will sometimes need a greater volume of hot water to be mixed with cold water in order to achieve the desired shower temperature.

Easily installed under a shower tray or a bathtub, the ZYPHO utilises the heat from the hot water flowing down the drain. Water entering the ZYPHO will transfer its heat energy to the copper pipe with cold mains water. Cold mains water going through the copper coil of the ZYPHO will, in turn, absorb this heat and therefore become warmer. After having passed through the heat exchanger, cool drain water then exits into the drainage system.

Preheated water goes to the shower mixer and, consequently, a smaller volume of hot water from your heating device is needed to reach an appropriate shower water temperature, which literally means that less energy is used.

The ZYPHO is a safe and clean system where hot shower waste water and cold water supply never mix. While allowing for easy maintenance and cleaning, its unique design also prevents pressure loss and leakage. The ZYPHO is distinguished by its exceptional reliability and durability due to the use of high-quality materials and a technology based on physical principles which are, despite their simplicity, innovative in this field of application.

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