EnerWorks Solar Water Heating Appliance
© 2011 EnerWorks Inc. - Page
49
-
Energy Kinetics Inc. / Installation
Manual
Controller operation
Differential Controller is a microprocessor-based control that monitors temperatures of solar collector and
of solar storage tank. If sufficient temperature difference for energy collection exists, Controller starts
pump. If sufficient temperature difference for energy collection no longer exists, Controller stops pump.
Temperature sensor, or thermistor, that measures temperature of water at bottom of solar storage tank has
two blue wires factory-connected to Common (
Com
) and Storage (
Stor
) terminals at lower right of
controller. Thermistor installed in solar collector must be connected via an 18-gauge two-wire control wire
that follows line-set to Energy Pack, and is connected to Common (
Com
) and Source (
Src
) terminals.
Thermistors are metal resistors with nominal 10 k
Ω
resistance at 77°F (25°C). Thermistor resistance
changes with temperature. As controller only monitors voltage drop across thermistor, negligible current
flows through thermistor. Any connections to Controller should be done with Energy Pack unplugged. Do
not connect or disconnect any wires to terminals at lower left of controller. Current flows through these
connections and there is a danger of shock and of damaging Controller.
Wired to storage tank’s upper thermostat (High-Performance (pre-heat) Appliances only), controller also
ensures that solar storage will not reach scalding or boiling temperatures. If thermostat setpoint is
reached, Controller will shut down pump and any further heat transfer.
Powering up
:
After Energy Pack is plugged in, LCD segments turn on for 3 seconds.
Settings
:
By pushing
Item
button, Controller cycles through following settings (controller continues to monitor and
control Energy Pack functions):
Item
Description
Δ
T (default)
Current temperature difference between Source (solar panel) and Storage (bottom
of solar storage tank) temperatures
Source
Current Source (solar panel) temperature
Storage
Current Storage (bottom of solar storage tank) temperature
Maximum Source
Maximum Source temperature since item was last cleared
Minimum Source
Minimum Source temperature since item was last cleared
Maximum Storage
Maximum Storage temperature since item was last cleared
Minimum Storage
Minimum Storage temperature since item was last cleared
HEAT
Number of relay running hours since item was last cleared