I have a water tower with an open loop condensing water system to plate heat exchanger then a closed loop in the building. Why? Also, there is a second heat exchanger (appears to be shell and tube). Why?
The cooling tower and plate combination is used to cool a chemical liquid in some process usually (in the closed loop)...Probably the same deal with the second exchanger. The shell and tube exchanger is usually used to heat or cool with water/steam in some chemical process... --to be more specific I would have to see more..or have a little better description.
