Pumping over

[Andymav]

Hi everyone we have an issue with the f@e tank it’s an open vent system gravity fed and the pump is pumping over into the f@e we had the the pipe work for the cold feed changed as it was clogged however it is still doing it even with the pump turned down it’s looking like the vent has been placed on the positive side of the the pump. Can the vent pipe be placed on the return or can we move the tee joint where the water goes up into the loft for the vent and place it elsewhere ? The tee connects into the cylinder then goes straight up.