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Alpha SolarSmart 100 - Component Replacement/Wiring Diagram
9 WIRING DIAGRAM
8.10 COLLECTOR TEMPERATURE SENSOR
The collector sensor is fitted into a pocket on the same side of the collector as the pipe connections (see Fig. 7 and 8).
To replace the sensor the cover plate will need to be removed from the side of the collector by removing the four retaining
screws. The old sensor can then be extracted from the pocket and the new one installed. Route the cable neatly through the
roof either under a tile or through the pipe hole and connect to the terminal block inside the roof space where the original
sensor was connected.
8.11 DBU HEAT EXCHANGER
Note:
Care must be taken when carrying out repairs to the DBU as it reaches very high temperatures and can emit steam
from connections when being removed.
Isolate the mains electric supply and remove the front case of the drain back unit by simply pulling it forwards.
Place a bucket under the drain plug at the bottom of the unit and using a suitable spanner, unscrew the plug while holding
the plug housing with another spanner to prevent damaging the pipe. Expect about 8 litres.
Loosen the flow and return connections beneath the drain back unit and slacken the locknuts. Disconnect the flow and return
pipes from the heat exchanger and remove them.
Remove the pipe from the heat exchanger to the pump. Loosen the pipe connection at the bottom of the cylinder then
disconnect the other end of the pipe from the heat exchanger and remove.
Withdraw the heat exchanger.
Reassemble in reverse order using new sealing washers. The heat exchanger can be fitted either way up.
Refer to Section 5.2 to refill the drain back unit.
8.12 BOILER INLET SENSOR
Isolate the mains electric supply.
The boiler inlet sensor is located on the inlet pipe to the boiler (see Fig. 1). Disconnect the wires from the sensor and unclip it
from the pipe.
Reassemble in reverse order. The polarity of the wires is not important.
Colour Code
Br Brown
Bk Black
Bl
Blue
G/Y Green/Yellow
Gy Grey
Br
Br
Bl
Bk
Bk Bk
Gy
G/y
Gy
Bl
Bl
Bl
Br
Br
Br
Bl
G/Y
G/Y
Supply
230 V ~ 50 Hz
13
12 46 45
70 69
Solar Cylinder
Pump
Optional Immersion Heater
Br
Bl
Upper
Cylinder
Sensor
Lower
Cylinder
Sensor
Solar
Collector
Probe
DBU Solar Pump
1
2
1
2
3
4
5
6
7
8
9
10
11
12
11
10
9
8
7
6
5
4
3
2
1
