Patent ID: 6622930
Filing Date: 2003-09-23
Classification: E03B,F16L,Y10T

Abstract:
Installation to prevent damage by freezing to hot or cold water pipes of a hot- and cold-water distribution system, characterized by a pipe (23) and a circulator pump (4) at the end of a hot water pipe (2) and a connection between the pressure side of circulator pump (4) and cold water pipe (3), the circulator pump (4) being energized by a temperature sensor (5) as soon as the temperature reaches a predetermined value near freezing and a check-valve between the pressure side of the pump and the cold water line and that in series with the check valve a hydraulically operated check valve which allows flow in the opposite direction of the check valve is arranged which will be opened by the pressure of pump and the pressure side of the pump contains a three-way valve and a re-circulation line.