We installed 2 new 1200 ton cooling towers. In doing so, we installed new CW piping, all of which is on a common header. There were 2 existing chillers that remained. There are 3 CWP's, 1 is standby. We installed 3 new VFD's for the pumps. We balanced the system through the pumps, one at a time...
In an effort to balance multiple CWP's through VFD's, the suction side of the pumps is drawing air. when we balanced through the pumps one at a time, this problem was not present. any thoughts?
