A rope is used as a combustible material in a heating system, the rope comprising or consisting of fibrous plant material. Also, a method of operating a heating system comprises feeding a combustible material to a combustion chamber of the heating system, the combustible material being a rope of fibrous plant material.

A furnace includes a pump in a circuit through a heat exchanger and a manifold having a plurality of discharge openings in a first area and return openings in a second area connected by a transfer area with each discharge and return feeding a respective heat loop. A bypass in the circuit includes a temperature controlled protection valve connected between the bypass and the manifold. The heated liquid inlet of the manifold is connected to the manifold in the first area with the plurality of discharge openings at a position between the plurality of discharge openings and the plurality of return openings. The manifold is defined by a rectangular chamber divided longitudinally and diagonally by a transverse wall which terminates at one end at a position spaced from an adjacent end of the chamber to define an undivided portion of the chamber at the end which forms the transfer area.

A manifold (15) comprising a flow chamber (35) for receiving flow heat exchange water from respective heat sources (3, 5, 7) through first inlet ports (47, 48) and from which the flow heat exchange water is delivered to heat exchange circuits (8, 9) through flow ports (57, 58). A return chamber (36) in the manifold (15) for receiving return heat exchange water from the heat exchange circuits (8, 9) through return ports (57, 58), and from which the return heat exchange water is returned to some of the heat sources (3, 5, 7) through first outlet ports (53, 54). A bypass chamber (37) located in the manifold (15) between the flow chamber (35) and the return chamber (36) receives flow water from the flow chamber (35), which has not been drawn off by the heat exchange circuits (8, 9), through a communicating passageway (40). Heat exchange water from the bypass chamber (37) is returned through second outlet ports (55, 56) to others of the heat sources (3, 5, 7).

The invention provides a use of a rope as a combustible material in a heating system, said rope comprising or consisting of fibrous plant material. The invention also provides a method of operating a heating system, comprising feeding a combustible material to a combustion chamber of the heating system, said combustible material being a rope of fibrous plant material.

A manifold (15) comprising a flow chamber (35) for receiving flow heat exchange water from respective heat sources (3, 5, 7) through first inlet ports (47, 48) and from which the flow heat exchange water is delivered to heat exchange circuits (8, 9) through flow ports (57, 58). A return chamber (36) in the manifold (15) for receiving return heat exchange water from the heat exchange circuits (8, 9) through return ports (57, 58), and from which the return heat exchange water is returned to some of the heat sources (3, 5, 7) through first outlet ports (53, 54). A bypass chamber (37) located in the manifold (15) between the flow chamber (35) and the return chamber (36) receives flow water from the flow chamber (35), which has not been drawn off by the heat exchange circuits (8, 9), through a communicating passageway (40). Heat exchange water from the bypass chamber (37) is returned through second outlet ports (55, 56) to others of the heat sources (3, 5, 7).