Newbie question about rated heat pump output

Thanks, that’s really clear. But how do you actually get that information? In the thread linked by @Timbones, the OP said the Daikin rep showed him a page in a book but wouldn’t give him a copy. I thought that was very strange.

The datasheets I have read don’t make a lot of sense. They talk about Tj values and pdh values at partial load but without any explanation. I think most people would just like a simple graph or table to show output against temperature, like the one above for the Ecodan. I am surprised that manufacturers don’t provide this information as a matter of course in the brochure or on the website. Surely, it’s the most basic information that a consumer needs i.e. will this heat pump actually provide enough power when it’s cold outside? It seems to be treated like a state secret!