Hydraulic unit

A multi zone heating system, comprising:

• a common heat source therefor;
• a pump;
• a plurality of heating zones, at least one of the plurality of heating zones having a plurality of sub-zones;
• and
• a hydraulic unit, wherein the hydraulic unit comprises:
• a plurality of independently controllable valves, each of the plurality of independently controllable valves being associated with a supply to each of the plurality of heating zones and operative to supply the at least one of the plurality of heating zones, and the plurality of sub-zones therewithin, with heated water from the common heat source-via the pump,
• a controller which operates the plurality of independently controllable valves and controls an output of the pump,
• a flow sensor,
• at least one temperature sensor, and
• a processor which receives a temperature signal from the at least one temperature sensor, associated with one of the plurality of heating zones, and a flow signal from the flow sensor, associated with the one of the plurality of heating zones,
• wherein the processor is operative to process the temperature signal and the flow signal in accordance with control software and to issue a command signal to the pump and to at least one of the plurality of independently controllable valves to vary a flow rate of water from the common heat source to the one of the plurality of heating zones associated with the flow signal and the temperature signal,
• whereby the at least one of the plurality of independently controllable valves is operable to divert heated water to the one of the plurality of heating zones in response to the temperature signal from the at least one temperature sensor associated with the one of the plurality of heating zones,
• wherein one or more of the plurality of sub-zones within the at least one of the plurality of heating zones includes one or more radiators having one or more modulating valves;
• and
• the processor is further configured to receive a pressure differential signal from a pressure differential sensor, process the temperature signal, and the flow signal in accordance with control software and issues command signals to the pump and the one or more modulating valves, to vary the flow rate of water from the common heat source to each of the plurality of heating zones independently one to another, thereby enabling the hydraulic unit to control balancing of heating of the plurality of sub-zones, and
• at least one of the plurality of independently controllable valves further comprises a flushing point to enable a selected one of the plurality of heating zones to be tapped.