Fitting for a radiator in a single duct heating system

Claim 1

In a single duct heating system, of the type in which a single main flow pipe serves for supplying heating water to a radiator and for returning water therefrom, a fitting for joining a radiator to the main flow pipe, said fitting being in the form of a housing comprising: (a) an inflow duct connected to the main flow pipe through a pipe union; (b) an inlet duct for the radiator veering off from the said inflow duct at an upward angle and connected to an inlet pipe for the radiator through a pipe union, said inlet duct defining an inlet axis; (c) an outflow duct connected to the main flow pipe through a pipe union, said outflow duct being a continuation of the inflow duct veering off therefrom in a downward direction and defining an outflow axis coaxial with said inlet axis; (d) a further pipe union for connection to a return conduit from the radiator, said pipe union being arranged with its axis perpendicular to the outflow axis of the outflow duct; (e) a return duct consisting of an open ended pipe section disposed within the housing, said pipe section being tightly fitted by one of its ends into the said further pipe union and by the other of its ends into the outflow duct and having a bend therein of substantially 90° so that the said ends are substantially perpendicular to each other, whereby the return flow from the radiator flows in the same direction as the outflow in the outflow duct.