Heat Pump Query

[frank]

I've got a ground source heat pump in for repair as one of the plate heat exchangers failed and filled the system with ground water.

The layout of the pipework, which I am having to replace seems a little odd.

If you follow the path of the liquid in each mode (heating and cooling) there appears to be a continuous loop bringing the second TEV in to play? The TEV's are externally equalised but I've left the equalisation line off the drawing for clarity.

Can anyone explain why this layout is made this way? - or is it a mistake?

Only one filter drier seems to be bugging me as well?

Confused?????????