Is The Floor Heating Pipe Hot in The Upper Water Pipe Or Down The Water Pipe

Strictly speaking, the upper and lower water pipes are the same heat, but in actual use, the temperature of the upper and lower water pipes will be higher than that of the lower water pipes. Because the water in the pipe first flows in from the inlet pipe and then passes through the return pipe, the temperature of the down pipe will not be as high as that of the up pipe due to time problems.