Patent ID: 9284721
Filing Date: 2016-03-15
CPC Classification: E03B,E03C,F24D,Y02B,Y10T

Claim Text:
1. A fluid flow control system comprising: a heating device for heating a fluid; a first flow path for providing the heated fluid from the heating device to a use region; a heat exchanger having a supply path adapted to receive fluid from a fluid supply and an outlet path adapted to receive fluid from the use region, whereby the fluid in the supply path is pre-heated by the fluid in the outlet path; a second flow path for providing the pre-heated fluid from the supply path of the heat exchanger to the heating device; a first flow modulating device for controlling a flow of fluid along the first flow path and therefore along the outlet path; and, a second flow modulating device for controlling a flow of pre-heated fluid along the supply path; wherein the system further comprises a flow control device adapted to control each of the first and second flow modulating devices such that, during use, the fluid flow rates or changes to/in said flow rates in the fluid supply path and outlet path of the heat exchanger correlate substantially in proportion; a bypass flow path for providing per-heated fluid from the supply bath to the use region, the bypass flow path being connected between the second flow path upstream of the heating device and the first flow path downstream of the heating device; and, a bypass flow modulating device for controlling the flow of fluid in the bypass path; wherein the flow control device is further adapted to control the bypass flow modulating device such that the flow rate in the bypass path is a function of the flow rate in at least one of the first flow path and the second flow path; wherein each of the first, second and bypass flow modulating devices are capable of providing a variable degree of fluid flow between a closed position in which fluid flow is prevented and a fully open position; wherein the control device is operative to cause the actuation of the first and second flow modulating devices proportionally to that of the bypass flow modulating device.