1 Sensor cable - low voltage
2 Power supply cable 230 V / 400 V
3 Heating circuit flow
4 Circuit B flow
5 Heating circuit return
6 Circuit B return (optional)
7 Return from boiler back-up
8 Domestic hot water outlet
9 Flow to boiler back-up
10 Domestic cold water inlet
11 3/8" refrigerant fluid connection – liquid line
12 5/8" refrigerant fluid connection – gas line
Fig.2 Symbols used on the connection
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