ReFH 2.3 supports two internal modelling engines: one that provides backwards compatibility with ReFH 2.2 (“the ReFH 2.2 model”) and one with the latest model engine and new features, such as observed rainfall and climate change factor modelling (“the ReFH 2.3 model”).
To use the ReFH 2.3 model you will need to import the latest version of the FEH Web Service catchment or point XML files labelled as suitable for use with ReFH 2.3+. These files includes the new BFIHOST19 catchment descriptor. These new format XML are available as a free download at any locations where Web Service users have previously purchased data.
If you load an earlier version XML file (pre-November 2019), or an existing project saved in the ReFH 2.2 software, ReFH 2 will only run the ReFH 2.2 model.
Please also see How do I know which ReFH2 model I’m using?