The boiler is equipped with a three-stage pump that is set to
stage 2 in the delivered condition.
The minimum circulation volume is ensured by a connection
line between the flow and return. An automatic overflow valve
and a manually adjustable bypass valve are integrated into
the connection line.
In the delivered condition, the bypass valve is fully opened
to "MAX". Closing the valve can increase the residual head
(see diagram).
3062087_1108
Selecting the pump stage
Fig.: Pump rate stages at the heating circuit pump
Stage 1
Stage 2
Stage 3
Bypass valve
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