In order to supply hot-water of a constant temperature in the
pipe under the slab, stored hot-water could be maintained at the
specified temperature through the boiler, heat exchanger, and
storage tank [12].
It is necessary to select the centre and measure the temperature
between the nearest section of the pipe and the nearest part to the
middle point of the room to analyze the heating conditions in
the room. Also, thermocouples are used to measure the temperatures
of the room, the wall and the ceiling in the centre of each part.
A thermocouple, 1.5 m above the ground, is used to gauge the room
temperature.
Fig. 6 shows a schematic diagram for the data acquisition
system. The on–off control between the thermal storage tank and
the heat exchanger could maintain the temperature of the hot
water in the tank. Hot-water at a constant temperature is sent
indoors to the slab pipe by the pump, and the returned water goes
back to the tank. At this moment, data for temperatures of supplied
water, returned water and each section of the room are saved in the
PC.