摘要 |
<p>A heating-cooling system has a plurality of users, a piping system subdivided into a plurality of zones in each of which a respective group of the users is connected in parallel, a heater or cooler having a supply line and a return line connected to the zones, a pump connected to the heater or cooler and to one of the lines for flowing a heat-exchange medium through the respective users, and respective flow-control valves connected in each of the zones for controlling flow of the medium therethrough and establishing in the respective zones a respective differential pressure. Flow in the zones is adjusted by controlling the respective valves to make a detected actual value of the differential pressure in the zone correspond to a set-point value previously detected and stored, with the differential pressure across each of the control valves being similarly feedback controlled.</p> |