| 摘要 |
<p>PCT No. PCT/DK89/00185 Sec. 371 Date Nov. 12, 1990 Sec. 102(e) Date Nov. 12, 1990 PCT Filed Aug. 2, 1989 PCT Pub. No. WO90/01657 PCT Pub. Date Feb. 22, 1990.A central heating plant (either single pipe or double pipe) supplies heat carrying fluid to several rooms, each having a radiator (5) provided with a thermostat valve (6). The plant has a differential pressure valve (11, 111) placed downstream of the radiators, with a closing device (24, 25) controlled by a membrane (23) for regulating the flow of heat carrying fluid in a passage (19) between an inlet (17) and an outlet (18). If the windows in several rooms are opened, the thermostat valves (6) will open, whereupon the differential pressure valve should regulate the combined flow, which a conventional valve cannot do since the pressure difference across the two surfaces of the membrane (23) is small even with full flow. This drawback is avoided by means of a differential pressure valve (11, 111) with an adjustable throttle (15) between the inlet (17) and the closing device (24, 25), and by adjusting the throttle, regardless of the pressure distribution, to allow the maximum amount of fluid to pass.</p> |
