I have a 250 ton 19DH Carrier centifugal chiller that we just installed a VFD on. At extreme low load circumstances we are having trouble with the chiller surging. My question is do you have any recommendations on how to correct this problem? I know that I can install a hot gas bypass, but I do not want to loss all efficency that we are getting from the VFD. Thanks for any feesable solutions.