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Shower Drain Heat Exchanger & Tankless Hot Water

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Hot Water Besides our solar hot water system (listed separately) we have both a GFX shower-drain-water heat exchanger and a Takagi Jr. tankless hot water heater. The GFX captures more than 50% of the heat that would otherwise be washed down the drain while taking a shower. Incoming cold water goes thru a coil that wraps around the drain pipe. As you take a shower, over 50% of the heat is transferred to the cold water heading toward both the heater and the cold water tap. While showering, you use more "cold" water because it is not so cold anymore! And the heater has less heating to do because the cold water starts out much warmer. Most days, the tankless hot water heater has very little to do! Because the water is preheated by both the GFX and the solar hot water system, the backup heater usually only kicks in a little bit during the winter. Thankfully these modern water heaters know what the water temperature is, and only fire up when needed, and only enough to raise the water to the set-point temperature.

Other Benefits:

The Takagi is a "sealed combustion" heater, meaning it draws combustion air from the outside (rather than the basement) and exhausts to the outside as well. This setup eliminates the risk of Carbon Dioxide poisoning.

Maintenance Requirements:

GFX - No Maintenance require! Tankless hot water heater - Flush every few years with CLR/water solution.

Efficiency or Sustainability Improvements:

low flow faucets and shower heads.

My Motivation:

A Brighter Future!


No Home should be without!

Experience with Installer:

self installed.

Open House Info:

Please see my Energy Efficiency listing for Tour details. Thanks!

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Bill LaBine - Avon - NY
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Bill LaBine - Avon - NY

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Bill LaBine - Avon - NY: Energy Efficiency
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