While working on the NFP for the slinky GHX model, I found that the current GHX model has one field that is mislabeled and another which is not used. The max flow rate variable here: https://github.com/NREL/EnergyPlus/blob/develop/src/EnergyPlus/GroundHeatExchangers.cc#L765, is not used and the design flow rate, here; https://github.com/NREL/EnergyPlus/blob/develop/src/EnergyPlus/GroundHeatExchangers.cc#L756, is labled as the max flow rate in the idd.