My heated floors run at about 30°C on a very cold day.
That seens to be normal on a cold day. Your floor heating should be fine. Once the moisture has had a chance to be evaporated, any operating temperature (within its range, of course) for a floor heating system should be ok. I suspect that the problem in the picture is that the moisture has been trapped inside the floor, because the floor tiles sealed it up.
When moisture cannot escape, it goes for the weakest point - in that case the floor surface, because it can’t go downwards (water vapor always rises up) and it can’t go sideways because of the walls of that room (the screed floor is between the walls). The temperature the floor heating could have been operated with didn’t need to be that high, just hight enough to make the remaining water start to change its aggregate state. Water vapor takes up more space than liquid.
The ammount of water that is brought into a buildung with concrete, screed, plaster, etc. (basically all material that has been a pile of dirt once) is often underestimated.
Water vapor absolutely can go down when under pressure. It goes in all directions in accordance with the pressure placed on it until it equalizes. In atmospheric conditions it tends to be more buoyant than air. But once it’s sealed it does wherever it faces the least resistance. You can put release valves facing down, it’s just also really stupid to do that because once released steam will just go up
That seens to be normal on a cold day. Your floor heating should be fine. Once the moisture has had a chance to be evaporated, any operating temperature (within its range, of course) for a floor heating system should be ok. I suspect that the problem in the picture is that the moisture has been trapped inside the floor, because the floor tiles sealed it up.
When moisture cannot escape, it goes for the weakest point - in that case the floor surface, because it can’t go downwards (water vapor always rises up) and it can’t go sideways because of the walls of that room (the screed floor is between the walls). The temperature the floor heating could have been operated with didn’t need to be that high, just hight enough to make the remaining water start to change its aggregate state. Water vapor takes up more space than liquid.
The ammount of water that is brought into a buildung with concrete, screed, plaster, etc. (basically all material that has been a pile of dirt once) is often underestimated.
Water vapor absolutely can go down when under pressure. It goes in all directions in accordance with the pressure placed on it until it equalizes. In atmospheric conditions it tends to be more buoyant than air. But once it’s sealed it does wherever it faces the least resistance. You can put release valves facing down, it’s just also really stupid to do that because once released steam will just go up