Др = Chapter 8, Problem 081 Water at 40 °F flows through the coils of the heat exchanger as shown in the Fig. P8.81 at a rate of 0.9 gal/min. Determine the pressure drop between the inlet and outlet of the horizontal device. psi st 13in Threaded 180° return bend 0.5-in. copper pipe (drawn tubing) Figure P8.81