Solar water, residential - Rated system size incorretly calculated

The equation for system_capacity he referred to is still shown in the GUI help for the solar water heating model. I am using that equation in my own program.  The Technical Manual for the solar water heating model (March 2014) is described as out of date on your website, but I haven't found anything saying exactly what is out of date about it.

Hi Russ,

The equation in the user interface on the Solar Water Heating input page for Rated System Size seems to be working in SAM 2021.12.02 r2 as described in Help.

For example, this screenshot shows inputs for Collector Area = 2.5 m2, FRta = 0.7, FRUL = 4, and Number of Collectors = 2.



The equation given in Help is:

Nameplate Capacity = Total Collector Area × ( FRta - FRUL × 30/1000 )

5 * ( 0.7 - 4 * 0.03 ) = 2.9

As for the manual being out of date, there have been changes to the code since then, but I'm not sure how significant they have been, and we haven't had the resources to review and revise the manual.

Thanks,
Paul.