Duplicating an DDVAV AHU in openstudio crashes model

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I am trying to model a building with around 15 AHU's and most of them are DDVAV feeding multiple zones but not symmetrical. So I thought of creating one AHU and use the duplicate button on OS to start the next with a copy of the AHU. But every time I hit duplicate 'x2', OS crashes. Is this possible approach or there is a limitation to duplicate coils and connections on OpenStudio?