Passive Solar Hot Water System
The Copperheart is a passive "batch" type collector that holds 20-40 gallons of water (depending
on the model) and is plumbed in-line before the water heater. Although it is usually used as a
pre-heater the system can be configured to bypass the water heater and send solar hot water straight
to the house. The thermal mass of the stored water provides some protection from freezing, but these
systems are recommended only in climates where the overnight low does not fall below 27 degrees
Fahrenheit. One advantage of the Copperheart is it has no moving parts, which means lower maintenance.
Drainback Solar Hot Water System
The Drainback system is a closed loop solar water heating system which uses water, rather than
anti-freeze or oil as a heat exchange medium. The system must be plumbed so the collector and
all piping slope back toward the storage tank and the drainback reservior tank so that when the
system shuts off, all of the water drains from the collector and piping so that no water is left
above the roof-line where it could freeze. An advantage of the drainback is the fact that the
heat-exchange fluid drains from above the roof when the system shuts off providing protection
from overheating as well as freezing.
Closed Loop "Glycol" Solar Hot Water System
Simple and effective, this system circulates non-toxic propylene glycol anti-freeze solution through
the solar collector and then the heat is transferred to the water tank by means of an internal heat
exchanger integrated within the storage tank. In addition to the heat exchanger the storage tank is
equipped with its own electric heating element for back-up heating, or the system can be used to
pre-heat for an existing gas water heater. Non-toxic propylene glycol provides 100% freeze protection.
When properly maintained, systems can last over 30 years. Automatic Differential Thermostatic Controls
make the system totally automated, and can be upgraded to include Internet connected Data Monitoring
equipment if desired.
All other types of Solar hot water systems are available