| With the three pipes system the water is pumped proportionally through the heat exchangers cooling and heating depending the position of the heating and cooling valves on the ceiling zone.
The temperature of the water supply to the hot exchanger will depend of the outside temperature same for the supply to the cold heat-exchanger.
Example : In winter at -10 outside the temperature of the secondary water to the ceiling can go up to 30°C and with a + 12°C outside temperature you will be satisfied with a secondary hot water at 22°C and a free cooled water from an aero-cooler at 15°C to the secondary cooling distribution.
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