How can I set the outlet temperature for Wateruse:Connections?

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I am designing a solar thermal system which feeds some DHW loads. I would like to set the temperature after the "Wateruse:connections" element that returns into the loop to 5 ºC but I am not sure how to do it. I have seen the "Watermains" object but I think this is for the input water, not for outlet. My system is very similar to the SolarCollectorFlatplateWater example file, and this one doesn't use Watermains or anything else and I didn't find where the temperature is set.

One solution is to use "Plantequipment:Temperaturesource", but I think it is not necessary.