This one probably requires opening an E+ issue. For the similar condition, though severe error is issued for chiller types EIR, reformulated EIR, central GSHP and other chillers such as electric, engine driven etc., fatal error is not issued and program runs to completion. Only ChillerHeater:Absorption:DoubleEffect and ChillerHeater:Absorption:DirectFired issue fatal error. The reason for condenser flow rate getting sized to zero could be chiller evaporator flow rate or nominal capacity or chilled water loop design volume flow rate are getting sized to zero. Unfortunately there don't seem to be a workaround except hard sizing inputs such as chiller nominal capacity and see if the file runs to completion.