<html><body><div style="color:#000; background-color:#fff; font-family:HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif;font-size:13px"><div id="yiv0256044417"><div id="yui_3_16_0_1_1427231173387_11855"><div style="color:#000;background-color:#fff;font-family:HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif;font-size:13px;" id="yui_3_16_0_1_1427231173387_11854"><div id="yiv0256044417"><div id="yiv0256044417yui_3_16_0_1_1427231173387_5536"><div style="color:#000;background-color:#fff;font-family:HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif;font-size:13px;" id="yiv0256044417yui_3_16_0_1_1427231173387_5535"><div id="yiv0256044417yui_3_16_0_1_1427231173387_2419" dir="ltr">Hi,</div><div id="yiv0256044417yui_3_16_0_1_1427231173387_2419" dir="ltr"><br></div><div id="yiv0256044417yui_3_16_0_1_1427231173387_2419" dir="ltr">I'm modelling underfloor heating system. The building has three floors, but it has underfloor heating only on the first two floors and the third is unheated. I made the active layers and in the first zone I have ground floor-boundary(with the active layer), on the second floor I made the ground floor(with active layer) adjacent to the first floor zone and on the third floor I made ground floor(without active layer) adjacent to the second floor zone , the roof as external surface. (All of the walls are made as external surfaces)</div><div id="yiv0256044417yui_3_16_0_1_1427231173387_2419" dir="ltr">First I tried just to get the required heating energy for the zones but I get warnings - when I remove the active layers then is possible to calculate the required heating energy.</div><div id="yiv0256044417yui_3_16_0_1_1427231173387_2419" dir="ltr"><br></div><div id="yiv0256044417yui_3_16_0_1_1427231173387_2419" dir="ltr"> Did I made some mistake with the adjacent zones or could be something else, any idea?</div><div id="yiv0256044417yui_3_16_0_1_1427231173387_2419" dir="ltr"><br></div><div id="yiv0256044417yui_3_16_0_1_1427231173387_2419" dir="ltr">Best Regards</div><div id="yiv0256044417yui_3_16_0_1_1427231173387_2419" dir="ltr">Igor </div></div></div></div></div></div></div></div></body></html>