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3 Product description
8
993x063x-mub-en – V01
2017/01
3.2.1
Check valve and non-return valve
The HeatBloC is equipped with a check valve (D-1, opening pressure 200 mm wc) in the return
pipe and with a non-return valve (C-3, opening pressure 50 mm wc) in the return of the mixing
valve. The valves can be opened.
Operation
During operation, the markings must point to "Z".
The check valve and the non-return valve are closed.
Flow only in the direction of the arrow.
Filling, draining, venting
For filling, draining and venting, the markings must be
directed to "A".
The check valve and the non-return valve are open.
Flow in both directions.