PAW SolarBloC midi Basic 2S Installation And Operation Instruction Manual page 13

4 Commissioning [specialist]
Functions of the fill and drain valve within the safety group
Position
09/2023
Function
Position "closed" (station in operation):
Fill and flush circuit is closed. Pressure gauge indicates system pressure.
Position "open" (fill and flush processes):
Fill and flush circuit is open. Pressure gauge indicates pressure.
Position "maintenance" (maintenance work):
Fill and flush circuit is closed. Pressure gauge indicates, after removal of
cap, no pressure.
Attention: Remove stop bolt before changing the position!
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