Problem Description

When we use ABD Mechanical or Plumbing Design design tools we get the errors:
 
Part and Family Defined for configuration variable HVAC_FAMILY_DUCT_DEFAULT not found

Part and Family Defined for configuration variable BMECH_FAMILY_PLUMBING_DEFAULT not found

Steps to Resolve

The following two variables set the default Family and Part for the tools.

In thecase of the GB Dataset they are set in the Dataset.cfg file found by default in:

C:\ProgramData\Bentley\AECOsimBuildingDesigner V8i Ss5\WorkSpace\BuildingDatasets\Dataset_GB.

The actual location of this file in a configured networked workspace will be different.
The values in the delivered file are:
HVAC_FAMILY_DUCT_DEFAULT = M-G5::M-G524 Ventilation
BMECH_FAMILY_PLUMBING_DEFAULT = M-G5::M-G501 Cold Water

Use Dataset Explorer to check that the two parts exist in the M-G5 section:
M-G524 Ventilation
M-G501 Cold Water

They are stored in file Mechanical_parts.xml whose default location is C:\ProgramData\Bentley\AECOsimBuildingDesigner V8i Ss5\WorkSpace\BuildingDatasets\Dataset_GB\part\, the actual path for your system will be shown in Dataset Explorer.

If these parts are not listed and this file is missing it would explain the error.