I think there is an error on the WaterHeaterMixed component. When I assigned it to HotWaterLoop I got an error: 1. Solution exception:Object reference not set to an instance of an object.
I use the latest version of Ladybug tools and Openstudio 3.6.1.
I know that @MingboPeng just pushed an updated version of Ironbug a couple of days ago. Are you using the latest version? If so, Mingbo can hopefully tell what is going on here.
@chris Thank you for your answer. Yes, I updated before I posted this issue. @MingboPeng Thank you for the instant response and for resolving the issue.