How it works

Renewable Heat From the Earth

The Commercial Water Heating system heats 2,500-3,000 gallons of water per day by using renewable heat from the earth. The system includes two circuits that converge in the heat pump unit: a refrigerant circuit that uses climate friendly R-407C refrigerant and a hot water circuit.

The Refrigerant Circuit

The refrigerant circuit includes a standard compressor, ETI’s proprietary refrigerant flow controls, and the highly conductive earth loops that circulate liquid refrigerant to harvest heat from the surrounding earth. As the liquid refrigerant is heated, it evaporates, expands and returns to the heat pump, passes through the proprietary vapor flow control (ACC), then to the compressor where its pressure and temperature are increased.

The hot refrigerant vapor travels through the heat exchanger where it gives up its heat to the cooler water on the other side of the double-wall heat exchanger. Having transferred its heat, the refrigerant condenses into a cold liquid, passes through the proprietary liquid flow control (LFC) that manages its flow back into the earth loops to repeat the process. The flow controls modulate the amount of refrigerant in circulation to assure the optimum efficiency at all times.

The earth loops can be installed vertically, diagonally or horizontally for maximum design flexibility and cost-effectiveness. They are factory charged with R-407C refrigerant and can be isolated from the heat pump unit for easy servicing by closing the refrigeration service valves.

The Water Circuit

The water circuit includes the heat exchanger, a small heavy-duty bronze water circulating pump, a mixing/storage tank for pre-heated water, and a standard electric or gas water heater tank.

As hot water is drawn from the building’s water piping circuit, city water enters the storage tank where it mixes with pre-heated water and is drawn through the heat exchanger that raises its temperature to approximately 120°F and it is then returned to the mixing/storage tank. As more hot water is used in the building, pre-heated water moves into the adjacent water heater tank where its temperature can be boosted above 120°F, if desired.

Simple and Efficient

The EarthLinked heat pump system is a simple and highly efficient method of harvesting renewable energy from the earth to heat large quantities of water for commercial and institutional users. It is the result of three decades of engineering design and field experience. In 1984, The Florida Solar Energy Center independently verified its ability to reduce energy consumption by 75% (read the report).

The unit is insulated to assure its quiet operation and to deliver all of its heat to the water tank. The powder-coated metal cabinet is 24” wide, 18” deep, and 26” high.