RESIDENTIAL DRAINBACK

 

There are nineparts to the Trendsetter system.  
A - Solar collectors- Trendsetter Evacuated tubes
B – Solar Storage tank- Non-pressurized insulated water storage tank
C - Heat exchanger- Stainless steel heat exchanger with high turbulence, ¾” connection size
D - Solar pump - Pumps water through solar panels
E - Solar controller – Turns solar pump on and off automatically
F - Tempering valve- A safety device to cool down the solar hot water if necessary
G - Water heater-Use existing water heater or replace with tank-less water heater

The solar storage tank (B) contains tap water.  One sensor is mounted at the solar collector (A) and one sensor is installed in a “dry dip tube” inside of the storage tank.   When the solar collector is hotter than the water in the storage tank, the solar controller (E) powers the solar pump (D).   The water is slowly circulated through the solar collector on the roof.  The water in the storage tank will gradually rise in temperature.  The water will rise 5°F-10°F in temperature between the time the water enters the solar collector and the time it leaves the solar collector. 

When hot water is used in the house, the cold water is pre-heated as it courses through the heat exchanger (C) immersed in the solar heated water stored in the insulated storage tank.   If the existing water heater is used as a back-up, the pre-heated water will reduce the energy normally needed to raise the water temperature entering the . water heater.  For example, if the cold water entering the water heater is 60°F, the water heater will require fuel to raise the incoming water from 60°F - 120°F (8,617 BTU per 100 gallons).  If the entering water temperature were raised to 100°F the fuel consumption would be reduced by 2/3rds.  The same 100 gallons of hot water would consume only 2,878 BTU’s

If a tank-less water heater replaces the conventional tank type water heater, the tank-less heater will flash on to raise the water temperature.  For example if the water temperature pre-heated by the solar, is 100°F the tank-less unit will provide just enough energy to boost the pre-heated water an additional 20°.

If the solar water in the tank reaches very hot or even scalding hot temperatures, incoming water will be drawn through the heat exchanger in the solar storage tank and through the tempering valve (F). The scalding hot solar water will be automatically mixed with cold water at the tempering valve to supply the desired 120°F (adjustable to 140°F) water temperature to the water heater.