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Solar Hot Water System

Components
Bubbling Springs Flat Plate Collector
Solar Skies Flat Plate Collector
BTF Solar Evacuated Tubes
2 IMC Solar Eagle 2 Differential Controller
iSeries Mixing Valve
Rehau Distribution Manifold
3 Grundfos Cast Iron Variable Speed Pump
Grundfos Stainless Steel Variable Speed Pump
Taco Temperature Controller
AET Drainback Tank
2 Expansion Tank
Bradford White 80gal Storage Tank

The first solar loop and hydroponic loop of our Solar Hot Water System was installed in the Fall of 2010. The second solar loop was added in the Fall of 2011.

Solar
Loop 1
The first solar loop to go up was a closed loop, pressurized propylene glycol system that used BTF Solar Evacuated Tubes. The fluid from this system is circulated by a Grundfos Cast Iron Variable Speed Pump into a 80gal Bradford White Storage Tank. The brains of this loop is the IMC Solar Eagle 2 Differential Controllerwhich tells the pump to kick on once there is a large enough difference in temperature between the solar collectors and storage tank.

Hydroponic Floor Heating Loop
This is the demand portion of the system. In this loop we take the heat generated from the collectors and pump it through the floor to heat the building. The fluid from the storage tank is circulated by another Grundfos Cast Iron Variable Speed Pump. The heated fluid is distributed through the floor in two circuits of PEX tubing by a Rehau Distribution Manifold. The brains of this system is a Taco Temperature Controller.

Solar Loop 2
This was the last addition to our solar hot water system. This solar loop is an open loop drainback system that utilizes Flat Plate Collectors by Bubbling Springs and Solar Skies. We wanted to be able to gauge the effectiveness of both solar thermal systems in our climate, so we used virtually identical components. In this case, the system is circulated by a Grundfos Stainless Steel Variable Speed Pump into a AET Drainback Tank. To use the heat generated by the collectors, we then connected the heat exchanger of the drainback tank to the hydroponic loop. This section Grundfos Cast Iron Variable Speed Pump. Similar to the other solar loop, the brains of this section is an IMC Solar Eagle 2 Differential Controller.

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