Ground heat exchanger

Abstract

The invention relates to a ground heat exchanger to be positioned in a borehole ( 1 ) in the ground. The ground heat exchanger ( 2 ) comprises a flow leg ( 3 ) and a heat exchanger leg ( 4 ). Yet further the ground heat exchanger ( 2 ) comprises a refilling pipe ( 9 ) that is permanently attached to a lower part of the ground heat exchanger ( 2 ).

1 . A ground heat exchanger to be positioned in a borehole in the ground,
 the ground heat exchanger comprising a flow leg,   a heat exchanger leg, and   at least one refilling pipe that is permanently attached to a lower part of the ground heat exchanger.   
     
     
         2 . Ground heat exchanger according to  claim 1 , comprising an upper manifold and a lower manifold to be positioned at the bottom of the borehole, the flow leg extending from the upper part of the borehole to the lower manifold, the heat exchanger leg comprising an outlet pipe extending upwards from the upper manifold and a plurality of heat exchanger pipes between the upper manifold and the lower manifold, the lower manifold connecting the flow leg and the heat exchanger leg. 
     
     
         3 . Ground heat exchanger according to  claim 2 , wherein the refilling pipe is attached to the flow leg in a position between the upper manifold and the lower manifold. 
     
     
         4 . Ground heat exchanger according to  claim 1 , wherein the refilling pipe comprises an optical marking for differentiating it from other pipes of the ground heat exchanger. 
     
     
         5 . Ground heat exchanger according to  claim 2 , wherein the refilling pipe comprises an optical marking for differentiating it from other pipes of the ground heat exchanger. 
     
     
         6 . Ground heat exchanger according to  claim 3 , wherein the refilling pipe comprises an optical marking for differentiating it from other pipes of the ground heat exchanger.