Hello,
We have a problem about the U-value of the windows described in Prebid. The value given by TRNSYS simulation does not match with the one we calculate ourselves.
For example, on a very basic building with only one window and no solar radiation at all, when Ug=1.3 W/(m².K), Uf=23.88 kJ/(h.m².K) and area of frame per window x=0.15, we calculate Uw=Ug*(1-x)+Uf/3.6*x=2.1 W/(m².K), and the u-win value output by Prebid is 1.81 W/(m².K).
Is there an explanation to these results and how can we be sure to give Prebid the right value of Uframe in ordert to get the right value of u-win (here (2.1 w/(m².K) )?
Thank you for answering.
Amelie MARILLER
ETAMINE -Vaulx en Velin- France