Central heating circuit with parallel return flows - has valve between pump and boiler giving return flow by=passing boiler

摘要

The central heating circuit with a boiler and circulating pump supplying a series of units such as radiators, includes a special valve acting as a mixer valve for a return line from the radiators. The valve is inserted between the boiler and the pump, and forms a straight through path between them, controlled by a valve member. A side branch forms a connection between a branch in the return line from the radiators. This forms two parallel return lines, one through the boiler, the other by passing it. The branch at the valve, controlling the return line by passing the boiler incorporates a swinging flap controlling the flow.