Alternative Energy Brochure

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© 2012 P 10006 - 09/12
Solar Thermal Applications
Storage
Tank
Sensor
Collector Sensor
Variable
Speed Pump
Heat Dump
Pump
Heat Dump
Electric
DHW
Difference Setpoint
Control 157
Inside
Outside
Solar DHW Pre-Heat & Heat Dump
Systems with a high solar capacity require an alternate place to
transfer heat if the storage tank starts to overheat. If the control
detects overheating, the pump to the heat exchanger is turned
on while the pump to the storage tank is turned off. If domestic
hot water requires more heat than the solar panel can provide,
an electric element in the second tank operates to boost the
temperature. Anti-freeze glycol provides freeze protection in the
exposed piping.
Booster
Pump
Drainback
Tank
System
Pump
Storage
Tank
Sensor
Collector Sensor
Inside
Outside
Difference Setpoint
Control 157
Solar Storage Tank with Drainback
The control measures the temperature difference between the solar
panel & storage tank. As the temperature difference increases, the
pump speed is increased. As the temperature difference decreases,
the pump speed is reduced to provide additional time for heat
transfer. This allows for continued heat transfer & lower electrical
consumption during off peak times. During freezing conditions,
fluid is left in the drainback tank. Once the temperature recovers,
a booster pump can be used to prime the system.
Pool
Pool
Sensor
Collector Sensor
Difference Setpoint
Control 156
Solar Pool Heating
The control measures the temperature difference between the solar
panel & the pool. When there is a large temperature difference, the
control powers the three way diverting valve to redirect water from
the pool to the solar panel to be heated. When the temperature
differential between the solar panel & the pool becomes too low, the
3-way diverting valve is de-energized and pool water again circulates
between the pool intake to the outlets. If the pool reaches the maximum
temperature limit, the 3-way diverting valve is de-energized.