Since OpenStudio generally does not import IDF HVAC, any syntax checks by the Importer on HVAC components could be considered unnecessary from the software developer's perspective.

For OpenStudio users, there is of course a trivial work-around, i.e. delete the object(s) which Openstudio Importer complains about, or correct specific input parameters of such objects.

In the above example, the air-to-water heatpump minimum temperature for operation was set to below zero degrees Celsius (along with an IDD file modification to allow this in EnergyPlus), which apparently was still illegal for OpenStudio. But after changeing the minimum temperature input, the OpenStudio import was successful.