EagleSun™
Closed Loop (Indirect) Solar Water Heating Systems
"I"
System - Differential Control
The “I” System is designed to accommodate
climates where freezing weather occurs more frequently.
Instead of water flowing through the collector, an antifreeze
solution is circulated. A heat exchanger is located
within the storage tank. This maximizes the heat transfer
from the antifreeze solution to the coldest water in
the storage tank.
The “I” System is known as an indirect
pumped system because the heat transfer solution, i.e.
antifreeze, is pumped through the collector in a closed
loop. It never comes in direct contact with the potable
water in the storage tank. The closed loop includes
the collector, connecting piping, pump, expansion tank,
and heat exchanger. In this design, the large heat exchager
coil wraps around the perimeter of the storage tank.
As in the “D” System, the differential
control determines when the pump should be activated
and deactivated.
The “IPV” System in similar to the “I”
System except that the energy needed to power the pump
is provided by a photovoltaic (PV) panel. The PV panel
converts sunlight into electricity which powers a DC
pump. The transfer fluid circulates through the system
only when the sun is shining.
The DC pump and PV are suitably matched to ensure optimum
performance. The pump starts when there is sufficient
solar radiation available to heat the thermal collector.
The pumping speed increases with the increase in the
amount of sunlight. This produces a flow rate matched
to the level of heat transfer required. The system then
shuts off when the available solar energy diminishes.
Photovoltaic
Indirect (Closed Loop)
"IPV" System (above)
EagleSun™ Drainback
Solar Water Heating Systems
"DB"
Drainback System
The “DB” System Provides a reliable method
for ensuring that the collectors and their pipelines
never freeze. This is done by removing all the water
from the collector(s) and piping when the system is
not producing heat. Freeze protection is provided when
the system is in the drain mode. Each time the pump
shuts off the water in the collector(s) and piping drains
into the insulated reservoir tank. To allow for complete
drainage the collector(s) and piping are mounted at
a slight angle. A sight glass attached to the reservoir
tank shows when the reservoir tank is full, indicating
that the collector(s) has been completely drained.
The differential control of the “DB” System
activates the pump using the same strategy as the “D”
System. The solution, distilled water or antifreeze,
circulates in a closed loop never coming in direct contact
wit the potable water in the storage tank. The closed
loop includes the collector, connecting piping, pump,
reservoir tank and heat exchanger. The heat exchanger
wraps around the perimeter of the storage tank heating
the potable water in the tank.
Sav'n'Sun DX Drainback System The Natural Solution for
Hot Water
Sav’nSun is a packaged, fully integrated residential
hot water system designed for the energy-minded homeowner
who wants both savings and leading-edge technology that
contributes to a cleaner environment.
Sav’nSun is delivered complete with AET collectors,
a 50, 80, or 120 gallon storage tank, top mounted Drainback
Reservoir with heat exchanger, freeze-protected drainback
design, fluid handling package, and back-up heating
element, making the system suitable for all climates.
A Retrofit Kit is also available to convert any existing
water heating system into a solar water heating system
using the Drainback Reservoir with heat exchanger and
Solar Collectors. Please contact AET for sizing information.
