The Lutfey Loop is a simple, cost effective, and highly efficient system to manage residential and commercial climate control and hot water needs.
Part 1: Insulated Tank
The insulated water tank stores hot water to be used in warming the house and heating potable water.
Part 2: Primary Heat Transfer System
A small pump moves water from the insulated water tank up to the attic where the water flows through a series of pipes and back down to the insulated tank. This setup uses the same components as traditional radiant floor heating setup that is adhered to the ceiling of the attic in between the rafters. This transfers heat from the attic to the insulated water tank and cools the house by preventing excessive heat buildup in the attic. Locating the tubing on the inside of the attic protects the tubing from the elements, reduces installation costs, and keeps unsightly equipment off the roof of the house.
Part 3: Potable Water Heat Transfer
Submersed in the insulated tank, this component preheats water for use in showers, washing machines, and so forth.
Part 4: Uninsulated Tank
Located in permanent thermal contact with the basement floor, this component is designed to provide a constant source of below-ground temperature water. This component is functionally equivalent to burying lengths of tubing underground (either horizontally or vertically) without the considerable expense of drilling holes or excavating large areas of land.
Part 5: Heating
The insulated tank stores heated water which can be used as a source for radiant floor heating or other water-based heating methods.
Part 6: Cooling
The uninsulated tank stores water that will be near the constant underground temperature of 55 degrees Fahrenheit. Depending on the conditions, this water could be used for several purposes such as providing an input for a ground source heat pump, cooling the interior of the structure, and preventing snow buildup on the roof.