... 3.Best choice for heat pumpWork Condition:1)Refrigerant side (Between the tube and shell):R22,R134a,R404a ... Max working pressure is 50 Bar.2)Water side (inside of the tube):Domestic water,tap water,antifreeze (glycol ... pump, and water-source heat pump. High Effciency of Heat Exchange:1)Use efficiency finned copper tube, ... the Smooth Tube,it is a important cause of high efficiency.2)Inside the tube is screw ...