I would like to interject something.
You probably do some coil design to a lesser extent, Andy. What about changing the evap set-up from the high end of meduim temp to the low end. 45F evap changed to a 15F evap on the same system. The condenser might come into play on a marginal system complicated by high ambient temps variation. You could easily cut the velocity through the coil in half giving 1/4 the pressure drop.
Just rambling here, but I am going to apply that change of condition to the pressure drop equation Prof gave us. (I though it was a lot of work when I had to solve it in college many years ago. )