IE20100581A1

IE20100581A1 - A control unit for a heating system

Info

Publication number: IE20100581A1
Application number: IE20100581A
Authority: IE
Inventors: Michael Stack; Noel Hannan
Original assignee: Waterford Foundry Inv S Ltd
Priority date: 2009-09-18
Filing date: 2010-09-17
Publication date: 2011-04-13
Also published as: GB2473684A; GB2473684B; GB201001483D0

Abstract

A control unit (1, 2) for a heating system (70) having at least two heating pipeworks (72) and (71, 73) and at least two energy sources for heating liquid circulating in the pipeworks, one being a renewable energy source such as a boiler stove (30) and the other a conventional energy source, such as a gas boiler (35). The control unit comprises a base panel (5), at least a pair of interconnected valves (4, 4a) mounted on the base panel and an electronic control module for controlling the valves. The first valve (4) is directly connected to the renewable energy source and the first heating pipework and the second valve (4a) is directly connected to the conventional energy source and the the second pipework. The electronic control module configured to control the valves so that the liquid heated by the renewable energy source is directed into the first and/or the second pipework and/or so that liquid heated by the second energy source is directed into the second heating pipework as and when determined by the electronic control module. <Figure 1>

Description

The present invention relates to a controi unit for a heating system, the heating system including at least two energy sources, such as, for example, but not in any way limited thereto, an automatic gas boiler and a boiler model stove.

Indoor central heating and hot water systems comprising two energy sources are known. For example, a dual central heating and hot water system is known comprising a central heating loop (i.e. a radiator loop) directly heated by a gas boiler. The radiator loop typically includes a heat exchanger located in a hot water tank (also known as cylinder) of a domestic hot water loop. The heat exchanger indirectly heats the water in the cylinder.

In a dual system, the water in the radiator loop pipework can also be heated by another source, for example, a boiler model stove (Le. a stove that has a bui|t—in boiler coii).

When the stove is in use for directly heating surrounding air, a portion of the energy released by the burning fuel in the stove is used to heat the water in the built—in boiler coil for circulation in the radiator loop and heating the radiators. The problem associated with such a dual system resides in the difficulty of controlling heat distribution in the heating system and the resulting inefficiency of the use of the available energy.

It is therefore an object of the present invention to provide a control unit for a heating system comprising at least two energy sources for controlling the heat and the flow in the heating circuits so as to reduce heat loss and use the available energy more efficiently.

Accordingly, the present invention provides a control unit for a heating system having at least two energy sources for heating liquid circulating within the system, the control unit comprising a base means and at least a pair of valves mounted on the base means, each valve having at least three ports; wherein a first port of a first valve is connectable to a pipework circuit of a first energy source for receiving liquid heated by the first energy source; a second port of the first valve is interconnected with a second port of the second a third port of the first valve is connectable to a first heating pipework for directing therein liquid received through the first port of the first valve; wherein a first port of the second valve is connectable to a pipework circuit of a second energy source for receiving liquid heated by the second energy source; a second port of the second valve is interconnected with the second port of the first valve; and a third port of the second valve is connectable to a second heating pipework for directing therein liquid received through the first or the second port of the second valve; and wherein the control unit comprises an electronic control module configured to control the flow through the at least first and second valves so that heat from liquid heated by the first energy source is directed into the first and/or the second heating pipework and/or so that heat from liquid heated by the second energy source is directed into the second heating pipework as and when determined by the electronic control module.

Preferably, each of the first and the second valves comprises at least one shut-off member operable to open and close at least one port. Ideally, each shut-off member is in electronic communication with and is controlled by the electronic control module to open or close the respective port in such a manner that heat from liquid heated by a desired first or second energy source is directed into the first and/or second heating pipework as and when determined by the electronic control module.

Ideally, the electronic control module is configured to control the valves and the second energy source and to monitor the operation of the first energy source in such a manner that when the first energy source is in operation and the heat supplied by the first energy source is sufficient, the second energy source is not in operation and the first port of the second valve is closed.

In this manner, when one energy source is in operation and the other is not in operation, backflow into the pipework leading to the other energy source is prevented, thereby preventing heat loss at undesired locations.

Furthermore, the electronic control module is conﬁgured to control the valves so that when the electronic control module determines overheating at the first energy source or in the first or second heating pipework, a port or ports connecting the first energy source with the other of the first and second heating pipework is opened so that heat from the first energy source is diverted to another pipework thereby providing for more efficient distribution of heat in the pipeworks of the heating system.

Preferably, the first heating pipework comprises a first hot water pipework and the second heating pipework comprises a central heating pipework and/or a second hot water pipework.

Preferably, when the first energy source is in operation, the first port of the second valve is closed and the electronic control module issues a command to the first valve to open the third port to permit flow into the first heating pipework; and/or to the first valve to open the second port and to the second valve to open the second and the third ports to permit ﬂow into the second heating pipework, as determined by the eiectronic control module.

Preferably, when the second energy source is in operation, the first port of the second valve is opened and heated liquid flows into the second heating pipework and the second port of the second valve is closed.

Advantageously, the electronic control module is configured to control the first and the second valves and at least one of the ﬁrst and the second energy sources, so that when it is detected by the electronic control module that heat provided by the currently operating energy source is insufficient, the other energy source is turned on and flow through the first port of the corresponding first or second valve is permitted, thereby providing additional heat to a relevant heating pipework. Further advantageously, the electronic control module is conﬁgured to control valves and at least one of the first and the second energy source, so that one heating pipework, for example the first heating pipework, is heated by the first energy source, whereas, simultaneously, another heating pipework, for example the second heating pipework, is heated by the second energy source. in one embodiment, the control unit of the invention includes a third valve comprising at least two ports, wherein a first port of the third valve is in communication with the third port of the second valve and a second port of the third valve is connectable to a third heating pipework for introducing therein liquid received through the first port of the third valve. The third valve is preferably mounted on the base means. lEroo5s1 In one preferred arrangement, the first energy source comprises a renewable energy source, such as, for example, a boiler model stove (i.e. a stove that has a built-in boiler coil for heating liquid flowing through the coil), or a solar panel; and the second energy source comprises a conventional energy source, such as a boiler (e.g. a gas boiler). In this arrangement, the renewable energy source is normally used unless it is not possible to operate the first energy source or the first energy source provides insufficient energy.

Accordingly, the electronic control module is preferably configured to monitor the operation of the first and the second energy sources so that when it is determined by the electronic control module that the energy form the second energy source is required (e.g. in the case when the first source has run out of fuel or the energy supplied by the first energy source is insufficient) the second energy source starts to operate and the first port of the second valve is opened to permit the ﬂow from the second energy source.

The electronic control module is configured to determine which pipework the flow is to be directed into and, accordingly, which port of which valve to open. The determination is made on the basis of, for example, signals received from various devices electronically connected to the electronic control module. These devices may comprise, for example, detector means provided at predetermined locations along the first, the second, the third (if applicable) and any further heating pipework of the heating system; a timer device; a relay device; a pre-programmed microprocessor or any other means as would be envisaged by a person skilled in the art.

The detector means provided at pre-determined locations along a pipework are preferably operable to measure heating parameters (e.g. temperature) at the pre- determined locations and to communicate the measured values or related data to the electronic control module.

Accordingly, in a preferred mode of operation of a heating system controlled by the control module of the invention, when one energy source is in operation and pre- determined heating parameters are met, the other energy source is not in operation.

Furthermore, in the event that there is no heat requesting signal communicated to the electronic control module from the detector means and the currently operating energy source has heated the liquid in the relevant pipework to a desired pre-determined level, lE10058l‘l‘ the electronic control module causes a port of a heating pipework which has remained closed to open to permit the transfer of heat to at least a portion of the previously closed heating pipework in order to prevent excessive temperature build up in the relevant heating pipework and distribute heat more efficiently.

In one modification, the first heating pipework comprises a first hot water pipework, the second heating pipework comprises a central heating system pipework and the third heating pipework comprises a second hot water pipework. Hereinafter, the first heating pipework will be referred to as a first hot water pipework; the second heating pipework will be referred to as a central heating system pipework; and the third heating pipework will be referred to as a second hot water pipework. It will be appreciated however that the valves of the control unit of the invention can be connected to various pipeworks in various combinations as would be apparent to a person skilled in the art, and the control unit of the invention is not limited to the use only with the above specified types of pipework or with the above specified combination.

Preferably, the control unit comprises first and second return ports through which the liquid returns into the first energy source. The control unit preferably also comprises third, fourth and fifth return ports through which the liquid which has completed its path through the heating pipeworks is re-circulated.

In one embodiment, the pipework of the first energy source and of the first hot water pipework are not in liquid communication with the pipeworks of the second energy source, the central heating system and the second hot water pipework. Such an arrangement may be required, for example, when the liquid in the second hot water pipework and in the central heating pipework and the liquid in the first not water pipework circulate under different pressures. For example, in one arrangement, the liquid in the first hot water pipework circulates under the influence of gravity and is open to the atmosphere, whereas the liquid in the second hot water pipework and the central heating pipework is not open to the atmosphere (i.e. sealed), and is propelled therethrough by a pump. Therefore, the liquid circulating through the ﬁrst energy source and through the first hot water pipework does not mix with the liquid circulating through the second energy source and through the second hot water pipework and the central heating system. In such an embodiment, ideally, a heat exchanger device is provided between the second ports of the first and the second valves for transfer of heat between the non-mixing liquids, so that the energy from IE 1005 81?‘ the first or the second energy source can be used in the pipework which is not in liquid communication with that energy source.

The heat exchanger in such an embodiment preferably comprises at least a pair of adjacent flow chambers hermetically separated from each other by a partition made of heat conductive material. Each chamber comprises a pair of ports. A first port of a first flow chamber is in liquid communication with the second port of the ﬁrst valve. The second port of the first flow chamber is in liquid communication with the second return port. A first port of the second flow chamber is in liquid communication with the third and the fifth return ports. The second port of the second flow chamber is in tiquid communication with the second port of the second valve. In a preferred modiﬁcation, a first pump is provided, preferably mounted on the base means. The first pump is preferably coupled with the first port of the second flow chamber at one end and with the third and the fifth return ports at the other end to facilitate flow from the return ports through the second flow chamber of the heat exchanger. A second pump is preferably mounted on the base means and is preferably coupled with the second port of the first flow chamber of the heat exchanger at one end and with the second return port at the other end to facilitate flow from the first flow chamber of the heat exchanger into the return port.

In this embodiment. when the first source of energy is in use, the liquid flows through the ﬁrst energy source and is heated by the first energy source to a pre-determined temperature. The heated liquid then enters the first port of the first valve. As determined by the electronic control module, one or both of the second and the third ports of the first valve are opened.

In one mode of operation, through the third port, the liquid flows into the first hot water The cooled liquid returns to the first source of energy via the first and the second return ports pipework, and becomes cooled by passing the heat to a liquid in a storage vessel. of the control unit.

In another mode of operation, through the second port of the first valve and through the first port of the heat exchanger, the liquid fiows into a first flow chamber of the heat exchanger where the energy of the liquid is conducted by the conductive partition to the liquid in the second chamber. Upon exit from the first flow chamber of the heat lE10o5a1 exchanger, the liquid returns to the first energy source via the second return port and repeats the cycle through the first energy source as detennined and controlled by the electronic control module. The second pump assists the circulation of the liquid through the first flow chamber of the heat exchanger. The liquid is supplied to the second flow chamber of the heat exchanger via the third return port from the second hot water pipework and/or via the fifth return port from the central heating system pipework. Having been heated in the second ﬂow chamber of the heat exchanger, the liquid exits the heat exchanger through the second port and enters the second port of the second valve and exits the second valve through the third port of the second valve. The first pump assists in this mode of operation of the control unit of the invention, the first port of the second valve the flovv of the liquid through the second flow chamber of the heat exchanger. remains closed while the second energy source (e.g. a gas boiler) is not in operation, ‘thereby preventing heat loss due to backflow. Upon exit from the second valve, the liquid flows into the pipework of central heating system and/or, as the case may be, via the third valve into the second hot water pipework. Having passed through the central heating system, the cooled liquid returns to the heat exchanger via the fifth return port and repeats the cycle through the heat exchanger as determined and controlled by the electronic control module. Having passed through the second hot water pipework, the cooled liquid returns to the heat exchanger via the third return port and repeats the cycle through the heat exchanger as determined and controlled by the electronic control module.

In another mode of operation of the control unit, when the second energy source is in use instead of the ﬁrst energy source, the liquid passing via the fifth return port from central heating system and/or, as the case may be, via the third port from the second hot water pipework passes through the fourth port to the second energy source and becomes heated. The first and the second pumps are not in operation in this mode. Preferably, the liquid is propelled through the second energy source by a third pump. The heated liquid then enters the ﬁrst port of the second valve and exits the second valve through the third port of the second valve. The second port of the second valve remains closed and there is no flow through the second ﬂow chamber of the heat exchanger, thereby preventing heat loss. Upon exit from third part of the second valve, the liquid flows into the pipework of central heating system and/or, as the case may be, via the third valve into the second hot water pipework. Having passed through the central heating system, the liquid returns to the second energy source via the fifth port and the fourth ports. Having passed through the second hot water pipework, the liquid returns to the second energy source via the third and the fourth ports. The liquid then repeats the cycle through the second energy source as determined and controlled by the electronic control module. At this time, the ﬁrst energy source is preferably not in operation and the first port of the first valve preferably remains closed.

If required, upon a determination made by the electronic control module and a subsequent appropriate command, the first energy source can be turned on and the first port and the third port of the first valve opened, to permit the liquid heated by the first energy source to circulate in the first hot water pipework, while the second ports of the first and the second valves remain closed.

Ideally, the first pump is capable to pump liquid in two opposite directions and therefore can be used instead of the third pump in the event of failure of the third pump.

In another embodiment, the first energy source pipework and the first hot water pipework are arranged in liquid communication with the pipeworks of the second energy source and of the central heating system. Such an arrangement may be possible when, for example, all the pipeworks of the heating system are open to the atmosphere and therefore liquid heated by the same energy source can be allowed to circulate through all the pipeworks. In this modification, liquid from more than one source can circulate through each pipework and different liquid propelling means can be utilised in the pipeworks. For example, liquid in the pipework of the first energy source and in the first hot water pipework can circulate under the influence of gravity and the liquid in the pipeworks of the second energy source and of the central heating system and the second hot water pipework can be propelled by a pump.

In such an embodiment, the energy from each energy source can be used for directly heating liquid which is subsequently circulated in any desired pipework circuit of the heating system. In this arrangement, the second port of the first valve is in liquid communication with the second port of the second valve so that heated liquid can flow Preferably, the third and fifth return ports are arranged in liquid communication with the second return port leading to the first from each energy source into a desired pipework. energy source. More specifically, the third and the fifth ports are preferably connected with second return port by means of an interchange pipework. The interchange pipework preferably comprises a length of pipework extending between the interconnected second lEroo5sr return port at one end and the interconnected third and fifth return ports at the other end.

Ideally, a fourth pump is built into the interchange pipework between the ends to facilitate the flow. The fourth pump is preferably mounted on the base means.

Accordingly, when the ﬁrst energy source is in use, the liquid flows through the first energy source, such as, for example, a boiler model stove, and becomes heated to a pre- determined temperature. The liquid then enters the first port of the first valve. As determined by the electronic control module, one or both of the second and the third ports Through the third port, the liquid flows into the first hot water pipework and becomes cooled by passing the heat to a liquid in a storage vessel. of the first valve are opened.

The cooled liquid then returns to the first energy source via the first and second return ports. The liquid then repeats the cycle through the first energy source as determined and controlled by the electronic control module.

In another mode, through the second port, the liquid exits the first valve, then enters the second port of the second valve and exits the second valve through the third port of the second valve. The first port of the second valve preferably remains closed while the second energy source (e.g. a gas boiler) is not in operation in order to prevent heat loss due to backflow. Upon exit from the second valve, the liquid flows into the pipework of the central heating system and/or, as the case may be, via the third valve into the second hot water pipework. Having passed through the central heating system, the liquid returns to the first energy source via the ﬁfth return port, through the interchange pipework and via the second return port and repeats the cycle through the first energy source as determined and controlled by the electronic control module. Having passed through the second hot water pipework, the liquid returns to the ﬁrst energy source via the third return port, through the interchange pipework and via the second return port and repeats the cycle through the first energy source as determined and controlled by the electronic control module. The fourth pump preferably facilitates the flow through the central heating system andlor the second hot water pipework and through the interchange pipework.

If required however, as desired by a user or upon a determination made by the electronic control module and upon an appropriate command issued by the etectronic control module, the first hot water pipework can be heated by the first energy source, whereas the central heating system and/or the second hot water pipework can be heated !E10o5 by the second energy source. In this case, one or both the second ports of the first and the second valves remain closed.

Preferably, when_the first energy source is not in operation, the second port of the second valve is closed in order to prevent heat loss caused by backflow.

In a further mode of operation, when the second energy source is in use, the liquid flows through the fourth return port to the second energy source and becomes heated to a pre-determined temperature. The liquid then enters the first port of the second valve and exits the second valve through the second or the third port of the second valve, as , determined by and controlled by the electronic control module. The second port of the first valve preferably remains closed while the first energy source is not in operation so as to prevent heat loss due to backflow. Upon exit from third port of the second valve, the liquid flows into the pipework of central heating system and/or, as the case may be, via the third valve into the second hot water pipework. Having passed through the central heating system, the liquid returns to the second energy source through the fifth return port and through the fourth return port and repeats the cycle through the second energy source as detennined and controlled by the electronic control module. Having passed through the second hot water pipework, the liquid returns to the second energy source through the third return port and through the fourth return port and repeats the cycle through the second energy source as determined and controlled by the electronic control module. The fourth pump preferably facilitates the flow through the central heating system andlor the second hot water pipework and through the interchange pipework.

The third pump preferably facilitates the flow through the second energy source.

In one embodiment, the first energy source comprises a boiler model stove and the second energy source comprises a gas boiler.

Preferably, the first and the second hot water pipeworks heat the liquid of the same liquid storage vessel.

The electronic control module is also configured to control a desired output of heat to the pre-determined locations via temperature measuring means. The temperature measuring means can comprise thermistors to measure the temperature in the hot water pipeworks and in the central heating system.

E10o5 In a preferred variation, the electronic control module is configured to control the components of the heating system in such a manner that liquid is normally heated by the first energy source and is used for heating liquid in the first or the second hot water pipework and of the central heating system. The second energy source is used as a back up source of energy in case the heat provided by the first energy source is insufﬁcient, in which case the second energy either operates concurrently with the first energy source, or in place of the first energy source, as described above.

If excess heat is detected in one of the hot water pipeworks or in the central heating pipework and the other pipework is not sufficiently heated or is not currently used, the electronic control module opens a relevant port of a relevant valve so that the excess heat is diverted to at least a portion of the pipework which is under-heated or is not currently in use, thereby providing for more optimal distribution of the available energy.

For example, in the first embodiment of the control unit, if during the operation the first energy source the temperature measured at the first energy source is below X °C, the heat provided by the first energy source is considered insufficient by the electronic control module. In this case, the electronic control module causes the second energy source to turn on, the first and second pumps to turn off and the second ports of the first and the second valves to close. The ﬁrst energy source can continue to operate through the first hot water pipework. Preferably, X equals 65.

Preferably, when temperature at the first energy source exceeds X °C, the heat supplied by the first energy source is considered sufficient, and the liquid from the first energy source is directed to heat the second hot water pipework and the central heating pipework.

Preferably, when the temperature at the first energy source is greater than X °C but less than Y "C and the temperature in a liquid storage vessel is less than X °C, the flow is diverted to the first hot water pipework. Preferably, Y equals 85.

Preferably, when the temperature at the first energy source is greater than X °C but the temperature at the liquid storage vessel is greater than X °C, the flow is diverted to one or more zones of the central heating pipework.

IE‘l0O5 Preferably, when the temperature at the first energy source is greater than Y °C but the temperature at the liquid storage vessel is greater than X °C, the flow is also diverted to one or more zones of the central heating pipework.

Preferably, when the temperature at the first energy source is greater than Y °C but the temperature at the liquid storage vessel is less than X °C, the flow is diverted to each of the first hot water pipework and one or more zones of the central heating pipework.

When the temperature at the first energy source is greater than the temperature at the third port of the second valve, and the temperature at the third port of the second valve is greater than Z °C, the second energy source is turned off and the electronic control module checks if the first energy source can provide enough heat to maintain the temperature in the second hot water pipework and in the central heating pipework.

Preferably, 2 equals 70.

The detector means preferably comprises programmable thermostats connected to the electronic control module.

The electronic control module preferably comprises a programmable electronic microprocessor.

An energy source (e.g. the gas boiler) can include a sleep button for disabling the energy source for a pre-set period of time and/or an LCD advising the status of the pre- determined locations if the detector means at those locations are calling for heat. The LCD can also display the status of the energy source and the temperature at the pre- determined locations.

In a further variation, the control unit is configured for connection with a third energy A source for delivering heat to one or each of the hot water pipeworks and the central heating pipework. In one variation, the third energy source comprises a further energy source, different from each of the first and second energy sources, such as, for example, a solar collector for heating liquid in a third hot water pipework which in turn heats liquid in the liquid storage vessel. The third energy source is controiled by the electronic control module in such a manner that when there is a sufficient of energy available in the third IE1005 energy source, upon receipt of an appropriate signal from a detector means of the third energy source, the electronic control module permits flow in the third hot water pipework.

In a modification where the third energy source can be subjected to severe weather conditions, such as, for example, frost, a fourth valve is provided for the purpose of protecting the third energy source from frost and a corresponding return pipework extending between one of the heating pipeworks of the heating system and the third energy source. Upon receipt of an appropriate signal from the detector means of the third energy source indicating that frost protection is required, the electronic controi module causes the fourth valve to open to permit the flow to the third energy source from a heating pipework of the heating system.

Additionally, the electronic control module of the control unit of the invention is also configured to control other auxiliary system, such as mechanical heat recovery ventilation, including bypass, timer control and ventilation speed control. The ventilation speed is controlled based on measurements of the moisture content of the air and the level of oxygen or carbon dioxide in the air, as communicated to the electronic control module from the relevant detector means.

The above described configuration of the control unit of the invention provides for easy plumbing of a heating system because all the relevant pipeworks are connected centrally with the ports provided on the base means of the control unit. The control unit of the invention provides for significant optimisation of heat usage by a heating system with no excess heat being directed to an energy source which is not in operation; and for the possibility of combining open and sealed plumbing systems, wherein each energy sources can be used for selectively heating any of the heating pipeworks of the heating system as determined and controlled by the electronic control module of the control unit of the invention. As described above, one of the energy sources can be used as a backup source of heat which starts operating when heat from the other energy source is insufficient. The control unit of the invention makes the plumbing of a combination heating system comprising at least two energy sources, such as an automatic gas boiler and a boiler model stove much simpler, safer and controllable and provides for intelligent control at multiple locations along the pipework of the heating system thereby providing for the most efficient use and distribution of the available energy and facilitating the prioritizing of a renewable energy source, such as the boiler model stove.

Accordingly, the invention provides a control unit for a heating system as defined in the appended claims.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS The present invention will now be described with reference to the accompanying drawings which show, by way of example only, embodiments of a control unit for a heating system according to the invention. In the drawings: Figure 1 is a perspective view of a first variation of the control unit of the invention; Figure 2 is another perspective view of the control unit of Figure 1; Figure 3 is an exploded perspective view of the control unit of Figure 1; Figure 4 is a perspective view of a second variation of the control unit of the invention; Figure 5 is an exploded perspective view of the control unit of Figure 4; and Figure 6 is a plan view of the control unit of Figures 4 and 5; Figures 7 to 10 are schematic illustrations of a heating system comprising the control unit of Figures 1 to 3 showing various modes of operation of the heating system; and Figures 11 to 13 are schematic illustrations of a heating system comprising the . control unit of Figures 4 to 6.

Referring to Figures 1 to 3 and 7 to 10. a first embodiment of the control unit in accordance with the invention is indicated generally by reference numeral 1 and comprises a base means in the form of a panel 5 on which the components of the control unit 1 are mounted.

Figures 4 to 6 and 11 to 13 illustrate a second embodiment of the control unit of the invention, which is indicated generally by reference numeral 2.

In Figures 1 to 13, like components have been indicated by like numerals.

On installation, the control unit 1, 2 is connected to various pipeworks of a combination heating system indicated generally by reference numeral 70 in Figures 7 to 13. The combination heating system includes at least two energy sources. lEioo5s1 As shown in Figures 7 to 13, a first energy source comprises a renewable energy source in the form of a boiler model stove 30, i.e. a stove that has a built-in boiler coil for heating water flowing through the coil. The second energy source comprises a conventional source of energy in the form of an automatic gas boiler 35. Water supplied into the boiler model stove 30 flows under the influence of gravity from a storage tank 74.

Water flowing through the automatic gas boiler is propelled by a boiler pump 36.

In the presently described embodiments, the heating system 70 includes a central heating circuit pipework 71, which comprises radiators 70, and ﬁrst and second hot water pipeworks 72 and 73 respectively. In the first hot water pipework 72, water circulates under the influence of gravity and in the second hot water pipework 73 the water is propelled by one or more pumpsas will be described below. Both hot water pipeworks 72 and 73 comprise heat exchanges 72a, 73a, respectively disposed inside a hot water storage cylinder 76.

The control unit 1, 2 also comprises a first valve 4, a second valve 4a and a third valve 4b. The valves 4, 4a, 4b comprise ports 41, 42, 43, 44, 45, 46, 47, 48 which are connected in a manner described below to the central heating circuit pipework 71 and to the hot water pipeworks 72, 73 of the heating system 70 when the control unit 1, 2 is installed. The valves 4, 4a, 4b control the flow in these pipeworks.

Valves 4, 4a and 4b are mounted on the base panel 5. The valves 4, 4a, 4b are controlled by an electronic control module 6 which has a built-in programmable microprocessor (not shown). The electronic control module 6 is conﬁgured to control the valves 4, 4a, 4b in accordance with heating parameters (e.g. temperature readings) set and/or measured at pre-determined locations or zones along the pipeworks of the heating system 70. The values of the heating parameters are communicated to the electronic control module 6 from detector means (not shown) provided at the pre-determined locations.

The electronic control module 6 is configured to control the flow through valves 4, 4a, 4b and the operation of the boiler model stove 30 and of the automatic gas boiler 35 in accordance with the pre-determined heating parameters set or measured at the pre- determined locations or zones so that water heated by one of the boiler modei stove 30 or IEroo5s1 the automatic gas boiler 35 or both is directed through the relevant valves 4, 4a, 4b into the relevant pipework 71, 72, 73 as will be described below.

In a preferred mode of operation of the heating system 70, the electronic control module controls the flow through the valves 4, 4a, 4b and the operation of the boiler model stove 30 and of the automatic gas boiler 35 such a manner that when one of the two energy sources, i.e. the boiler model stove 30 or the automatic gas boiler 35 is in operation and the pre-determined heating parameters are met, a port of a valve that enables the communication with the other energy source is closed, thereby reducing energy loss.

Normally, a renewable energy source, i.e. the boiler model stove 30, is used for heating water either in the first hot water pipework 72 or in one or both of the second hot water pipework 73 and in the central heating pipework 71. The automatic gas boiler 35 is normally used as a back up source of heat in case the heat provided by the boiler model stove 30 is insufficient, or in the case e.g. when the boiler model stove 30 has run out of fuel or is out of order, or when additional heat is required (either as desired by a user or in accordance with a pre-determined signal received from the detector means), in which case the gas boiler 35 either operates concurrently with the boiler model stove 30, or instead of the boiler model stove 30. Accordingly, the electronic control module 6 is also configured to control the valves 4, 4a, 4band the automatic gas boiler 35 so that when the boiler model stove 30 is in operation and additional heat is required, relevant port or ports 41, 42, 43, 44, 45, 46, 47, 48 of the valves 4, 4a, 4b are opened to permit the flow from the automatic gas boiler 35 to one or both of the second hot water pipework 73 and in the central heating pipework 71.

If overheating is detected at the boiler model stove 30 and one or all of the hot water pipework 72, 73 or the central heating pipework 71 are not sufficiently heated or not currently used, the electronic control module 6 opens a relevant port or ports 41, 42, 43, 44, 45, 46, 47, 48 of a relevant valve 4, 4a, 4b so that the extra heat is diverted to at least a portion of a pipework which is under-heated or not currently in use. In this way, excessive temperature build up at the boiler model stove 30 is prevented and more optimal energy distribution is achieved.

In the event of a power out or other failure, such as a failure of the pump 36 of the automatic gas boiler 35, the electronic control module 6 switches off the automatic gas boiler 35 and disables the pumped flow whereby only the flow through the boiler model stove 30 remains permitted. An audible warning signal is issued in such an event to warn the user not to refuel the boiler model stove 30 as refuelling may cause overheating at the boiler model stove 30, which cannot be corrected by the electronic control module 6 by diverting the flow from the boiler model stove 30.

The first valve 4 has three ports, namely, a first port 41, a second port 42 and a third port 43. The first port 41 of the first valve 4 is connectable on installation to a pipework circuit 75 of the first energy source, i.e. the boiler model stove 30, for receiving water heated by the boiler model stove 30. The third port 43 of the first valve 4 is connectable to the first hot water pipework 71, hereinafter referred to as the gravity flow hot water pipework, for directing therein water received through the first port 41. In the control unit 1 of Figures 1 to 3 and 7 to 10, the second port 42 of the first valve 4 is interconnected with a second port 45 of the second valve 4a by means of a heat exchanger 7 as will be described below. In the control unit 2 of Figures 4 to 6 and 11 to 13, the second port 42 of the first valve 4 is arranged in liquid communication with the second port 45 of the second valve 4a via a length of pipe 50 as will be described below.

The second valve 4a has three ports, namely, a first port 44, a second port 45 and a third port 46. The first port 44 of the second valve 4a is connected on installation to a pipework circuit 77 of the second energy source, i.e. the automatic gas boiler 35, for receiving water heated by the automatic gas boiler 35. In the control unit 1 of Figures 1 to 3 and 7 to 10, the second port 45 of the second valve 4a is interconnected with the second port 42 of the first valve 4 via the heat exchanger 7 as will be described below. In the control unit 2 of Figures 4 to 6 and 11 to 13, the second valve 4a is interconnected with the second port 42 of the first valve 4 by the length of pipe 50. The third port 46 of the second valve 4a is connected on installation to the central heating pipework 71 via a port 49 and to the second hot water pipework 73 via the third valve 4b, for directing therein water received through the ﬁrst port 44 or the second port 45 of the second valve 4a. lE1oo5e1 The third valve 4b comprises a first port 47 connected with the third port 46 of the second valve 4a, and a second port 48 connectable to the second hot water pipework 73 for introducing therein water received through the first port 47 of the third valve 4b.

Each of the first, the second and the third valves 4, 4a, 4b comprises a shut-off member (not shown) movable to open or close the ports 42, 43 of the first valve 4, the ports 44, 45 of the second valve 4a and one of the ports 47, 48 of the third valve 4b.

Each shut-off member is in electronic communication with and is controlled by the electronic control module 6.

The electronic control module 6 is conﬁgured to issue commands in the form of electronic signals to a relevant shut-off member to open or close the respective port 42, 43, 44, 45, in such a manner that when the boiler model stove 30 is in operation, flow though the first port 41 and through the second port 42 and/or the third port 43 of the first valve 4 is established and the first port 44 of the second valve 4a is closed; and when the automatic gas boiler 35 is in operation, flow through the first port 44 and the third port 46 is established; and the second port 42 of the first valve 4 is closed. In this manner, when one energy source is in operation, concurrent use of the two energy sources is prevented and transfer of heat from one energy source into the pipework leading to the other energy source is prevented, thereby reducing heat loss at undesired locations.

In another mode of operation, if it is detected by the electronic control module that heat provided by the boiler model stove 30 is insufficient, the automatic gas boiler 35 is turned on and the first port 44 of the second valve 4a is opened, thereby providing additional heat to the relevant pipework.

The electronic control module 6 is configured to determine which of the pipeworks 71, 72, 73 the flow from an energy source is to be directed into and, accordingly, which of the shut-off members appropriate signals are to be sent to. The determination is made on the basis of, for exampie, signals received from various devices electronically connected to the electronic control module 6. These devices comprise temperature detector means, such as thermistors, provided at predetermined locations of the heating system 70; a timer device; a relay device; a pre—programmed microprocessor. Other detector means would be readily envisaged by a person skilled in the art. The detector means measure heating parameters at the pre—determined locations and communicate the measured lE1oo5e1 values or related data to the electronic control module 6, as will be described below. A shown in Figures 7 to 13, in the presently described embodiments, thermistors are installed at the boiler model stove out—feed pipe 75a (A), in-feed pipe 75b (B), inside the cylinder 76 (C) and at the third port 46 of the second valve 4a (D).

Normally, in the functioning of the heating system 70 preference is given to the boiler model stove 30 which sends the heated water to the pump-assisted second hot water pipework 73 and the central heating pipework 71. The automatic gas boiler 35 is used when the boiler model stove 30 is not in operation or when the heat provided by the boiler model stove 30 is insufficient. if overheating is detected at the boiler model stove 30, and one or more of the pipeworks 72, 72, 73, or portions thereof are not in use, the electronic control module 6 controls the relevant valve to send some of the water heated by the boiler model stove 30 into the unused pipework. The automatic gas boiler 35 can be turned on upon a command of the electronic control module 6 if the heat is insufficient in the pipework into which the water has been diverted, and operate concurrently with the boiler model stove 30. The water form the storage tank 74 facilitates the cooling of the overheated water in the boiler model stove 30. In the first hot water pipework 72, the water circulates under gravity and the first hot water pipework 72 is used when it is not possible to use the heat from the boiler model stove 30 to heat the water in the second hot water pipework 73 and the central heating pipework 71 because of a power cut or another failure affecting the circulation of water in these pipeworks.

As shown in Figures 1 to 6, the control unit 1, 2 comprises return ports 51, 52 through which water returns into the pipework 75 of the boiler model stove 30. The control unit 1, 2 also comprises return ports 53, 54 and 55 through which the water which has completed its path through the pipework 71, 72, 73 is re-circulated as will be described below.

The control unit 1 of Figures 1 to 3 and Figures 7 to 10 is designed to be installed in a heating system in which the second hot water pipework 73 and the central heating pipework 71 are not open to the atmosphere, i.e. they are sealed, and the first hot water pipework 72 is open to the atmosphere. in this embodiment, the pipework 75 of the boiler model stove 30 and of the first hot water pipework 71 are not in liquid communication with the pipework 77 of the automatic gas boiler 35, the second hot water pipework 73 and the central heating system pipework 71. Therefore, the water circulating through the boiler model stove 30 and through the first hot water pipework 71 does not mix with the water circulating through the automatic gas boiler 35, the second hot water pipework 73 and through the central heating system pipework 71. The heat exchanger 7 is provided between the second ports 42 and 45, respectively, of the first and the second valves 4 and 4a for transfer of heat from the water heated by the boiler model stove 30 and to the water in the second hot water pipework 73 and to the central heating system pipework 71.

The heat exchanger 7 comprises adjacent ﬂow chambers (not shown) hermetically separated from each other by a partition (not shown) made of a heat conductive material.

A first port 60 of a first flow chamber is in liquid communication with the second port 41 of the first valve 4. The Each chamber comprises a pair of ports 60, 61 and 62, 63. second port 61 of the first flow chamber is in liquid communication with the return port 52.

A first port 63 of the second flow chamber is in liquid communication with the return ports 53 and 55. The second port 62 of the second flow chamber of the heat exchanger 7 is in liquid communication with the second port 45 of the second valve 4a.

A first pump 80 is mounted on the base panel 5. The first pump 80 is coupled with the first port 63 of the second flow chamber of the heat exchanger 7 at one end and with the return ports 53 and 55 at the other end. The first pump 80 facilitates ﬂow from the return ports 53 and 55 through the second ﬂow chamber of the heat exchanger 7.

A second pump 81 is mounted on the base panel 5 coupled with the second port 61 of the first flow chamber 60 of the heat exchanger 7 at one end and with the return port 52 at the other end. The second pump 81 facilitates flow from the first flow chamber of the heat exchanger 7 into the return port 52. in the control unit 1 of Figures 1 to 3 and Figures 7 to 10. the water that filts the pipework 75 of the boiler model stove 30 and the first not water pipework 72 is supplied on installation of the heating system 70 from the storage tank 74 as shown in Figures 7 to 13 and remains in circulation during the use of the heating system 30. The storage tank 74 nevertheless remains in communication with the boiler stove in-feed pipe 75b.

When the boiler model stove 30 is in operation, the water heated in the boiler model stove 30 expands and exits the boiler model stove 30, flows through the out-feed pipe 75a and enters the first port 41 of the first valve 4. As detennined by the electronic control lE1005 module 6, one or both of the second and the third ports 42 and 43, respectively, of the first valve 4 are opened.

In one mode of operation, as indicated by arrows in Figure 7, through the third port 43, the heated water flows into the first hot water pipework 72, passes through the heat exchanger 72a in the water cylinder 76 and heats the water in the water cylinder 76. The cooled water then returns to the boiler model stove 30 via the return ports 51 and 52 (see Figures 1 to 3) and along the in—feed pipe 75b of the boiler model stove pipework 75. The water then repeats the cycle through the boiler model stove 30 as determined and controlled by the electronic control module 6.

In another mode of operation, as indicated by arrows in Figures 8 and 9, through the second port 42 of the first valve 4 and through the first port 60 of the first flow chamber of the heat exchanger 7, the water flows into the first flow chamber of the heat exchanger 7 where heat is conducted by the conductive partition to the water in the second flow chamber of the heat exchanger 7. The pump 81 facilitates the flow. Upon exit from the first flow chamber of the heat exchanger 7 through the second port 61, the water returns the boiler model stove 30 via the return port 52 and via the in-feed pipe 75b of the boiler model stove pipework 72. The water then repeats the cycle through the boiler model stove 30 as determined and controlled by the electronic control module 6.

Into the second flow chamber of the heat exchanger 7, the water is supplied through the first port 63 of the second flow chamber of the heat exchanger 7 from the return port 53 from the second hot water pipework 73 and from the return port 55 from central heating system pipework 71. The pump 80 facilitates the flow. Having been heated in the heat exchanger, the water exits second flow chamber of the heat exchanger 7 through the second port 62 and enters the second port 45 of the second valve 4a. The water exits the second valve 4a through the third port 46 of the second valve 4a.

In the mode of operation shown in Figure 8, upon exit from the second valve 4a, the water ﬂows into the second hot water pipework 73 via ports 47 and 48 of the third valve 4b, passes through the heat exchanger 73a in the water cylinder 76 and heats the water ' in the water cylinder 76. The cooled water then returns into the second flow chamber of the heat exchanger 7 via the return port 53 (see Figures 1 to 3) for re—circu|ation. lE‘l005 In the mode of operation shown in Figure 9, upon exit from the second valve 4a, the water flows into central heating system pipework 71 and passes through radiators 78 thereby heating the surrounding air. The cooled water then returns into the second fiow chamber of the heat exchanger 7 via the return port 55 (see Figures 1 to 3) for re- Valves 900 control the flow to separate zones 100, 200, 30, 400 of the central heating system pipework 71. As indicated by arrows in Figure 9, flow is open into circulation. zone 100 in the present example.

The modes of operation shown in Figures 8 and 9 can run simultaneously.

In the modes of operation of the control unit 1 illustrated in Figures 8 and 9, the first port 44 of the second valve 4a remains closed while the automatic gas boiler 35 is not in operation in order to prevent heat loss which wouid othenivise occur caused by backflow into the pipework 77 of the automatic gas boiler 35.

In another mode of operation of the control unit 1, as illustrated in Figure 10, when the automatic gas boiler 35 is in use instead of the boiler model stove 30, the water supplied from the return port 53 from the second hot water pipework 73 and from the return port 55 from the central heating system pipework 71 flows through the return port 54 into the automatic gas boiler 35 and becomes heated. The first and the second pumps 80 and 81, respectively, are not in operation in this mode, and the water is propelled through the automatic gas boiler 35 by the boiler pump 36. The water heated in the automatic gas boiler 35 then enters the first port 44 of the second valve 4a and exits the second valve 4a through the third port 46. The second port 45 of the second valve 4a remains closed and there is no flow through the second flow chamber of the heat exchanger 7 in order to prevent heat loss.

Upon exit from third port 46 of the second valve 4a, the water flows into the second hot water pipework 73 and into the central heating system pipework 71 in the same manner as described with reference to Figures 8 and 9, respectively. Although Figure 10 iilustrates concurrent flow through the second hot water pipework 73 and the central heating system pipework 71, valves 4b and 900 can be controlled accordingly so that only one of the second hot water pipework 73 and the central heating system pipework 71 are in operation. The water returns to the automatic gas boiler 35 via the return ports 53, 55 and 54 for re-circulation as determined and controlled by the electronic control module 6. lE1005 The first pump 80 can pump water in both directions and can function instead of the pump 36 in case the pump 36 fails to propel the water through the automatic gas boiler 36.

The modes of operation of Figure 7 and Figure 10 can run simultaneously.

The heat exchanger 7 can be of any suitable type as would be apparent to a person skilled in the art, such as for example, but not limited thereto, a plate heat exchanger type or a shell-and-tube type.

The control unit 2 of Figures 4 to 6 and 11 to 13 is designed to be instalied in a heating system in which the central heating pipework 71 and the ﬁrst and the second hot water pipeworks 72, 73, respectively, are open to the atmosphere. in such a system, the boiler model stove pipework 75 and the first hot water pipework 72 are arranged in liquid communication with the pipework 77 of the automatic gas boiler 35, the central heating pipework 71 and the second hot water pipework73. in such a system all the pipeworks of the heating system 70 are open to the atmosphere and therefore, in principle, water heated by any of the boiler model stove 30 and the automatic gas boiier 35 can be allowed to circulate through all the pipeworks 71, 72, 73, 75 and 77. In such a system, energy from each energy source, i.e. each of the boiler model stove 30 and the automatic gas boiler 35 can be used for directly heating water circulated in the first and second hot water pipeworks 72, 73, respectively and the central heating pipework 71. in the control unit 2 of Figures 4 to 6 and 11 to 13, the second port 42 of the first valve 4 is in liquid communication with the second port 45 of the second valve 4a so that heated water can flow from the boiler model stove 30 though the second valve 4a into a desired pipework 71, 73. Also, the return ports 53 and 55, respectively, are arranged in liquid communication with the return port 52 leading to boiler model stove 30. More specifically, ports 53 and 55 are connected with return port 52 by means of an interchange pipework 90. The interchange pipework 90 comprises a length of pipework extending between the interconnected return port 52 at one end and the interconnected return ports 53 and 55 at the other end. A pump 91 is built into the interchange pipework 90 between the ends to facilitate the flow. The pump 91 is mounted on the base panel 5. lE10058‘l in the control unit 2 of Figures 4 to 6 and Figures 11 to 13, the water that fills the pipework 75 of the boiler model stove 30, the first and second hot water pipeworks 72, 73, the central heating pipework 71 and the pipework 77 of the automatic gas boiler 35 is supplied on installation of the heating system 70 from the storage tank 74 as shown in Figures 7 to 13 and remains in circulation during the use of the heating system 30. The storage tank 74 nevertheless remains in communication with the boiler stove in-feed pipe 75b.

When the boiler model stove 30 is in use, the water ﬂows through the boiler model stove 30, and becomes heated. The heated water expands and exits the boiler model -stove 30 through the out-feed pipe 75a and enters the first port 41 of the first valve 4. As determined by the electronic control module 6, one or both of the second and the third ports 42 and 43, respectively, of the first valve 4 are opened.

As shown in Figure 11, through the third port 43, the water flows into the first not water pipework 72, passes through the heat exchanger 72a in the water cylinder 76 and heats the water in the water cylinder 76. The cooled water then returns to the boiler model stove 30 via the return ports 51 and 52 and the in-feed pipe 75b of the boiler model stove pipework 75. The water then repeats the cycle through the boiler model stove 30 as determined and controlled by the electronic control module 6.

As shown in Figure 12, through the second port 42, the water exits the first valve 4, then enters the second port 45 of the second valve 4a and exits the second valve 4a through the third port 46. The ﬁrst port 44 of the second valve 4a remains closed while the automatic gas boiler 35 is not in operation in order to prevent heat loss which would otherwise occur caused by backflow into the pipework 77 of the automatic gas boiler 35.

Upon exit from the third port 46 of the second valve 4a, the water flows into the second hot water pipework 73 and into the centrai heating system pipework 71 in the same manner as described with reference to Figures 8, 9 and 10. The water then flows via the return port 53 from the second hot water pipework 73 and via the return port 55 from central heating system pipework 71 into the interchange pipework 90 through the port 52 into the in-feed pipe 75b and into the boiler model stove 30. Pump 91 facilitates the circulation through the interchange pipework 90 and through the second hot water pipework 73 and the central heating system pipework 71. The water then repeats the IE 1005 above described cycle through the boiler model stove 30 as detemiined and controlled by the electronic control module 6.

As shown in Figure 13, when the automatic gas boiler 35 is in use, the water flows through the return port 54 into the pipework 77 of the automatic gas boiler 35 and subsequently through the automatic gas boiler 35. The water heated by the automatic gas boiler 35 then enters the first port 44 of the second valve 4a and exits the second valve 4a through the third port 46 of the second valve 4a. While the boiler model stove is not in operation, the second port 45 of the second valve 4a is closed in order to prevent heat loss caused by backflow.

Upon exit from the third port 46 of the second valve 4a, the water flows into the pipework 71 of central heating system andlor via the third valve 4b into the second hot water pipework 73 in the same manner as described with reference to Figures 8, 9, 10 and 12. The water then flows via the return port 53 from the second hot water pipework 73 and via the return port 55 from central heating system pipework 71 through the return port 54 into the automatic gas boiler 35 and repeats the above described cycle. in the presently described examples, the electronic control module comprises a programmable electronic microprocessor.

With reference to the control unit 1 of Figures 1 to 3 and 7 to 10, during the operation the boiler model stove 30, when the temperature measured at A and B is below 65 °C, the heat provided by the boiler model stove 30 is considered insufficient. In this case, the electronic control module 6 causes the automatic boiler 35 to turn on, the pumps 80 and 81 to turn off and the ports 42 and 45 to close. The boiler model stove 30 can continue to operate through the first hot water pipework 72.

When temperature at either A or B exceeds 65 °C, the heat supplied by the boiler model stove 30 is considered sufficient, and the water from the stove is pumped through the heat exchanger 7 to heat the second hot water pipework 73 and the central heating pipework 71.

In the event that all the detector means at the relevant zones are in the position where there is no requirement for heat, then the flow can be diverted to either the first hot lE1005 water pipework 72 or one or more zones of the central heating pipework 71 as described below.

When the temperature at A is greater than 65 °C but less than 85 °C and the temperature at C is less than 65 °C, the flow is diverted to the first hot water pipework 72.

When the temperature at A is greater than 65 °C but the temperature at C is greater than 65 °C, the flow is diverted to one or more zones of the central heating pipework 71.

When the temperature at A is greater than 85 °C but the temperature at C is greater than 65 °C, the flow is diverted to one or more zones of the central heating pipework 71.

When the temperature at A is greater than 85 °C but the temperature at C is less than 65 °C, the flow is diverted to each of the first hot water pipework 72 and one or more zones of the central heating pipework 71.

When the temperature at A is greater than the temperature at D and the temperature at D is greater than 70 °C, the automatic boiler 35 is turned off and the electronic control module 6 checks if the boiler model stove 30 can provide enough heat to maintain the temperature in the pipeworks 73, 71.

Similar considerations apply to the control unit 2 of Figures 4 to 6 and 11 to 13.

The control unit 1, 2 can be provided with a button by pressing which the automatic settings of the gas boiler 35 are overridden and the automatic gas boiler 35 is disabled for a set period of time, e.g. 6 hours. if the button is pressed twice in quick succession it will disable the automatic gas boiler 35 until the button is pressed again.

In a further variation (shown in Figures 7 to 13), the heating system 70 comprises a third energy source for delivering heat to the water cylinder 76. in the present example, the third energy source comprises a solar collector 85. The solar collector comprises a third hot water pipework 86 which includes a third heat exchanger 86a inside the water cylinder 76. The electronic control module 6 is configured to control the operation of the solar collector 85 in such a manner that when there is a sufficient of energy available at the solar collector 85, the water in the water cylinder 76 is heated by the solar collector via |E10058‘l the third heat exchanger 86a. The thermistor (0) allows the electronic control module 6 to determine whether or not any additional heat is required in the water cylinder 76 which can be supplied if required from the boiler model stove 30 or the automatic gas boiler.

In order to protect the solar collector 85 from frost, upon receipt of an appropriate signal from a detector means provided at the solar collector 85 indicating that frost protection is required. the electronic control module 6 causes a pump 87 to activate the flow through the third hot water pipework 86 so that heat from the water in the water cylinder 76 is transferred via the heat exchanger 86a to the water in the third hot water pipework 86 and to the solar collector 85.

Additionally, the electronic control module 6 of the control unit 1, 2 of the invention is configured to control other auxiliary systems (not shown), such as mechanical heat The ventilation speed is controlled based on measurements of the moisture content of the air recovery ventilation, including bypass, timer control and ventilation speed control. and the level of oxygen or carbon dioxide in the air, as communicated to the electronic control module 6 from the relevant detector means.

The above described control unit 1, 2 provides for the possibility of combining in a heating system a renewable energy source, such as a boiler model stove 30, and a conventional energy source such as an automatic gas boiler 35, wherein the renewable energy source is used as a primary energy source and the conventional energy source is used to provide additional heat if the heat from the primary energy source is insufficient of unavailable and wherein the renewable energy source includes an auxiliary heating circuit operable under the influence of gravity which is used when flow through primary heating circuits is not possible (e.g. due to pump failures or power cuts).

The above described configuration of the control unit 1, 2 of the invention provides for easy plumbing of a heating system because all the relevant pipeworks are connected centrally with ports for connecting with the pipeworks being provided on the base panel 5 of the control unit 1, 2.

The control unit of the invention provides for significant optimisation of heat usage by a heating system with no excess heat being directed to an energy source which is not in operation; and for the possibility of combining open and sealed plumbing systems, iE1005 wherein each energy sources can be used for selectively heating the relevant pipeworks of the heating system as determined and controlled by the electronic control module 6 of the control unit 1, 2 of the invention.

The control unit of the invention makes the plumbing of a combination heating system comprising at least two energy sources, such as an automatic gas boiler and a boiler model stove much simpler, safer and controllable and provides for intelligent control at multiple locations along the pipework of the heating system thereby providing for the most efficient use and distribution of the available energy and facilitating the prioritizing of a renewable energy source, such as the boiler model stove.

It is thought that the present invention and its advantages will be understood from the foregoing description and it will be apparent that various changes may be made thereto without departing from the scope of the invention, the forms hereinbefore described being merely preferred or exemplary embodiments thereof, the invention being defined in the appended claims.

Claims

CLAIMS:

1. A control unit for a heating system having at least two energy sources for heating liquid circulating within the system, the control unit comprising a base means and at least a pair of valves mounted on the base means, each valve having at least three ports; wherein a first port of a first valve is connectable to a pipework circuit of a first energy source for receiving liquid heated by the first energy source; a second port of the first valve is -interconnected with a second port of the second valve; and a third port of the first valve is connectable to a first heating pipework for directing therein liquid received through the first port of the first valve; wherein a first port of the second valve is connectable to a pipework circuit of a second energy source for receiving liquid heated by the second energy source; a second port of the second valve is interconnected with the second port of the first valve; and a third port of the second valve is connectable to a second heating pipework for directing therein liquid received through the first or the second port of the second valve; and wherein the control unit comprises an electronic control module configured to control the flow through the at least first and second valves so that heat from liquid heated by the first energy source is directed into the first and/or the second heating pipework and/or so that heat from liquid heated by the second energy source is directed into the second heating pipework as and when determined by the electronic control module.

2. A control unit as claimed in Claim 1, wherein each of the first and the second valves comprises at least one shut—off member operable to open and close at least one port, wherein each shut-off member is in electronic communication with and is controlled by the electronic control module to open or close the respective port in such a manner that heat from liquid heated by a desired ﬁrst or second energy source is directed into the first and/or second heating pipework as and when determined by the electronic control module.

3. A control unit as claimed in Claim 1 or Claim 2, wherein the electronic control module is configured to control the valves and the second energy source and to monitor 35 lE1oo5a1 30 the operation of the first energy source in such a manner that when the first energy source is in operation and the heat supplied by the first energy source is sufficient, the second energy source is not in operation and the first port of the second valve is closed.

4. A control unit as claimed in any preceding claim, wherein the electronic control module is configured to control the valves so that when the electronic control module detemiines overheating at the first energy source or in the ﬁrst or second heating pipework, a relevant port or ports connecting the first energy source with the other of the first and second heating pipework is opened so that heat from the first energy source is diverted to another pipework thereby providing for more efﬁcient distribution of heat in the pipeworks of the heating system.

5. A control unit as claimed in any preceding claim, wherein the first heating pipework comprises a first hot water pipework and the second heating pipework comprises a central heating pipework and/or a second hot water pipework.

6. A control unit as claimed in any preceding claim, wherein, the control unit is configured so that during the operation the first energy source, the first port of the second valve is closed and the electronic control module issues a command to the first valve to open the third port to pemiit flow into the first heating pipework; and/or to the first valve to open the second port and to the second valve to open the second and the third ports to permit flow into the second heating pipework, as determined by the electronic control module.

7. A control unit as claimed in any preceding claim, wherein the controi unit is configured so that during the operation of the second energy source, the first port of the second valve is opened upon a command issued by the electronic control module and heated liquid flows into the second heating pipework and the second port of the second valve is closed.

8. A control unit as claimed in any preceding claim, wherein the electronic control module is configured to control the ﬁrst and the second valves and at least one of the first and the second energy sources, so that when it is detected by the electronic control module that heat provided by the currently operating energy source is insufficient, the other energy source is turned on and flow through the first port of the corresponding first or second valve is permitted, thereby providing additional heat to a relevant heating pipework. _

9. A control unit as claimed in any preceding claim, wherein the electronic control module is configured to control the valves and at least one of the first and the second energy source, so that one heating pipework, for example the first heating pipework, is heated by the first energy source, whereas, simultaneously, another heating pipework, for example the second heating pipework, is heated by the second energy source.

10. A control unit as claimed in any preceding claim, wherein the first energy source comprises a renewable energy source, and the second energy source comprises a conventional energy source.

11. A control unit as claimed in Claim 10, wherein the renewable energy source comprises a boiler model stove, and the conventional energy source comprises a gas boiler.

12. A control unit as claimed in Claim 10, wherein the control unit is configured to control the heating system so that the renewable energy source is normally used unless it is not possible to operate the first energy source or the first energy source provides insufficient energy.

13. A control unit as claimed in Claim 12, wherein the electronic control module is configured to monitor the operation of the first and the second energy sources so that when it is determined by the electronic control module that the energy form the second energy source is required, the second energy source starts to operate and the first port of the second valve is opened to permit the flow from the second energy source.

14. A control unit as claimed in any preceding claim, wherein electronic control module is configured to determine which pipework the flow is to be directed into and, accordingly, which port of which valve to open on the basis of signals received from various devices electronically connected to the electronic control module, the devices comprising one or more of detector means provided at predetermined locations the heating pipeworks of the heating system.

15. pre-determined locations along a pipework are operable to measure heating parameters, A control unit as claimed in Claim 14, wherein the detector means provided at the such as temperature, at the pre-determined locations and to communicate the measured values or related data to the electronic control module.

16. configured to control a heating system so that in one mode of operation of the heating A control unit as claimed in Claim 14 or Claim 15, wherein the control unit is system, when one energy source is in operation and pre-determined heating parameters are met, the other energy source is not in operation.

17. A control unit as claimed in Claim 14 or Claim 15, wherein the control unit is conﬁgured to control a heating system so that in the event that there is no heat requesting signal communicated to the electronic control module from the detector means and the currently operating energy source has heated the liquid in the relevant pipework to a desired pre-determined level, the electronic control module causes a port of a heating pipework which has remained closed to open to permit the transfer of heat to at least a portion of the previously closed heating pipework in order to prevent excessive temperature build up in the relevant heating pipework and distribute heat more efficiently.

18. a third valve comprising at least two ports, wherein a first port of the third valve is in A control unit as claimed in any preceding claim, wherein the control unit includes communication with the third port of the second valve and a second port of the third valve is connectable to a third heating pipework for introducing therein liquid received through the first port of the third valve.

19. A control unit as claimed in Claim 18, wherein the third valve is mounted on the base means.

20. A controt unit as claimed in Claim 18, wherein the first heating pipework comprises a first hot water pipework, the second heating pipework comprises a central heating system pipework and the third heating pipework comprises a second hot water pipework.

21. A control unit as claimed in Claim 20, wherein the control unit comprises first and second return ports through which the liquid returns into the first energy source; and third, fourth and fifth return ports through which the liquid which has completed its path through the heating pipeworks is re-circulated.

22. A control unit as claimed in Claim 21, wherein the contro! unit is configured so that the pipeworks of the first energy source and of the first hot water pipework are not in liquid communication with the pipeworks of the second energy source, the central heating system and the second hot water pipework.

23. A control unit as claimed in Claim 22, wherein the liquid in the second hot water pipework and in the central heating pipework and the liquid in the first hot water pipework circulate under different pressures.

24. A control unit as claimed in Claim 23, wherein the liquid in the first hot water pipework circulates under the inﬂuence of gravity and is open to the atmosphere, whereas the liquid in the second hot water pipework and the central heating pipework is not open to the atmosphere (i.e. sealed), and is propelled therethrough by a pump, wherein the liquid circulating through the first energy source and through the first hot water pipework does not mix with the liquid circulating through the second energy source and through the second hot water pipework and the central heating system.

25. A control unit as claimed in Claim 23 or Claim 24, wherein a heat exchanger device is provided between the second ports of the first and the second valves for transfer of heat between the non-mixing liquids, so that the energy from the first or the second energy source can be used in the pipework which is not in liquid communication with that energy source.

26. A control unit as claimed in Claim 25, wherein the heat exchanger comprises at least a pair of adjacent flow chambers hermetically separated from each other by a partition made of heat conductive material, each chamber comprising a pair of ports, wherein a first port of a first flow chamber is in liquid communication with the second port of the first valve and the second port of the first flow chamber is in liquid communication with the second return port; wherein a first port of the second ﬂow chamber is in liquid communication with the third and the fifth return ports; and wherein the second port of the second ﬂow chamber is in liquid communication with the second port of the second valve.

27. A control unit as claimed in Claim 26, wherein a first pump is provided, preferably mounted on the base means, the first pump being coupled with the first port of the second flow chamber at one end and with the third and the fifth return ports at the other end to facilitate flow from the return ports through the second flow chamber of the heat exchanger; and wherein a second pump is preferably mounted on the base means and is preferably coupled with the second port of the first flow chamber of the heat exchanger at one end and with the second return port at the other end to facilitate flow from the first flow chamber of the heat exchanger into the return port.

28. A control unit as claimed in Claim 27, wherein the control unit is configured to control the heating system so that when the first source of energy is in use and the liquid flows through the first energy source and becomes heated by the first energy source to a pre-determined temperature and then enters the first port of the first valve, electronic control module one or both of the second and the third ports of the first valve as determined by the electronic control module;

29. A control unit as claimed in Claim 28, wherein the control unit is configured to control the heating system so that through the third port, the liquid flows into the first hot water pipework, and becomes cooled by passing the heat to a liquid in a storage vessel; and whereby the cooled liquid returns to the ﬁrst energy source via the first and the second return ports of the control unit;

30. A control unit as claimed in Claim 28 or Claim 29, wherein the control unit is configured to control the heating system so that through the second port of the first valve and through the first port of the heat exchanger, the liquid flows into a first flow chamber of the heat exchanger where the energy of the liquid is conducted by the conductive partition to the liquid in the second chamber; whereby upon exit from the first flow chamber of the heat exchanger, the liquid returns to the first energy source via the second return port and repeats the cycle through the first energy source as determined and controlled by the electronic control module; whereby the liquid is supplied to the second flow chamber of the heat exchanger via the third return port from the second hot water pipework and/or via the fifth return port from the central heating system pipework; whereby having been heated in the second flow chamber of the heat exchanger, the liquid exits the heat exchanger through the second port and enters the second port of the second valve and exits the second valve through the third port of the second valve. 35 [E 1005

31. A control unit as claimed in any one of Claims 28 to 30, wherein the control unit is configured to control the heating system so that the ﬁrst port of the second valve remains closed while the second energy source is not in operation, thereby preventing heat loss due to backftow.

32. A control unit as claimed in Claim 28, wherein the second pump assists the circulation of the liquid through the first flow chamber of the heat exchanger and the first pump assists the flow of the liquid through the second flow chamber of the heat exchanger.

33. A control unit as claimed in any one of Claims 28 to claim 32, wherein the control unit is configured to control the heating system so that upon exit from the second vatve, the liquid flows into the pipework of central heating system and/or, as the case may be, via the third valve into the second hot water pipework; whereby having passed through the central heating system, the cooled liquid returns to the heat exchanger via the fifth return port and repeats the cycle through the heat exchanger as determined and controlled by the electronic control module; whereby having passed through the second hot water pipework, the cooled liquid returns to the heat exchanger via the third return port and repeats the cycle through the heat exchanger as determined and controlled by the electronic control module.

34. A control unit as claimed in Claim 27, wherein the control unit is configured to control the heating system so that when the second energy source is in use instead of the first energy source, the liquid passing via the fifth return port from central heating system and/or, as the case may be, via the third port from the second hot water pipework passes through the fourth port to the second energy source and becomes heated; wherein the heated liquid then enters the first port of the second valve and exits the second valve through the third port of the second valve.; whereby the second port of the second valve remains closed and there is no flow through the second flow chamber of the heat exchanger, thereby preventing heat loss; whereby upon exit from the third port of the second valve, the liquid flows into the pipework of central heating system and/or, as the case may be, via the third valve into the second hot water pipework; whereby having passed through the central heating system, the liquid returns to the second energy source via the ﬁfth port and the fourth ports; whereby having passed through the second hot 35 lE1005 water pipework, the liquid returns to the second energy source via the third and the fourth ports; wherein the liquid then repeats the cycle through the second energy source as determined and controlled by the electronic control module.

35. A control unit as claimed in Claim 34, wherein, the liquid is propelled through the second energy source by a third pump.

36. A control unit as claimed in Claim 34, wherein the control unit is configured to control the heating system so that the first energy source is not in operation and the first port of the first valve remains closed.

37. A control unit as claimed in Claim 34, wherein the control unit is configured to control the heating system so that upon a determination made by the electronic control module and a subsequent command, the first energy source is turned on and the first port and the third port of the ﬁrst valve are opened, to permit the liquid heated by the first energy source to circulate in the first hot water pipework, while the second ports of the first and the second valves remain closed.

38. A control unit as claimed in Claim 35, wherein the first pump is capable to pump liquid in two opposite directions and therefore can be used instead of the third pump in the event of failure of the third pump.

39. A control unit as claimed in Claim 21, wherein the control unit is configured so that the ﬁrst energy source pipework and the first hot water pipework are arranged in liquid communication with the pipeworks of the second energy source and of the central heating system.

40. A control unit as claimed in Claim 39, wherein all the pipeworks of the heating system are open to the atmosphere and wherein liquid heated by the same energy source can be allowed to circulate through all the pipeworks so that liquid from more than one source can circulate through each pipework and different liquid propelling means can be utilised in the pipeworks.

41. A control unit as claimed in Claim 40, wherein liquid in the pipework of the first energy source and in the first hot water pipework circulates under the influence of gravity 35 IE 1005 and the liquid in the pipeworks of the second energy source and of the central heating system and the second hot water pipework are propelled by a pump.

42. A control unit as claimed in Claim 39, wherein the second port of the ﬁrst valve is in liquid communication with the second port of the second valve so that heated liquid can flow from each energy source into a desired pipework.

43. A control unit as claimed in Claim 42, wherein the third and fifth return ports are arranged in liquid communication with the second return port leading to the first energy SOLIFCS.

44. A control unit as claimed in Claim 43, wherein, the third and the fifth ports are connected with second return port by means of an interchange pipework.

45. A control unit as claimed in Claim 44, wherein the interchange pipework preferably comprises a length of pipework extending between the interconnected second return port at one end and the interconnected third and fifth return ports at the other end.

46. A control unit as claimed in Claim 44, wherein the control unit is configured to control the heating system so that when the first energy source is in use, the liquid flows through the first energy source and becomes heated to a pre-determined temperature; wherein the liquid then enters the first port of the first valve; whereby as determined by the electronic control module, one or both of the second and the third ports of the first valve are opened.

47. A control unit as claimed in Claim 46, wherein the control unit is configured to control the heating system so that through the third port, the liquid flows into the first hot water pipework and becomes cooled by passing the heat to a liquid in a storage vessel; wherein the cooled liquid returns to the first energy source via the first and second return ports; and wherein the liquid repeats the cycle through the first energy source as determined and controlled by the electronic control module

48. A control unit as claimed in Claim 46 or Claim 47, wherein the control unit is configured to control the heating system so that through the second port, the liquid exits the first valve, then enters the second port of the second valve and exits the second valve E 1005 through the third port of the second valve; wherein upon exit from the second valve, the liquid flows into the pipewcrk of the central heating system and/or, as the case may be, via the third valve into the second hot water pipework; wherein having passed through the central heating system, the liquid returns to the first energy source via the fifth return port, through the interchange pipewcrk and via the second return port and repeats the cycle through the first energy source as determined and controlled by the electronic control module; wherein having passed through the second hot water pipewcrk, the liquid returns to the first energy source via the third return port, through the interchange pipewcrk and via the second return port and repeats the cycle through the first energy source as determined and controlled by the electronic control module.

49. A control unit as claimed in any one of Claims 46 to Claim 48, wherein the control unit is configured to control the heating system so that the first port of the second valve remains closed while the second energy source is not in operation in order to prevent heat loss due to backflow.

50. A control unit as claimed in Claim 44, wherein a fourth pump is built into the interchange pipewcrk between the ends to facilitate the flow.

51. A control unit as claimed in Claim 50, wherein the fourth pump is mounted on the base means.

52. A control unit as claimed in Claim 51, wherein the fourth pump facilitates the flow through the central heating system and/or the second hot water pipewcrk and through the interchange pipework.

53. A control unit as claimed in Claim 40, wherein the control unit is configured to control the heating system so that as desired by a user or upon a determination made by the electronic control module and upon an appropriate command issued by the electronic control module, the first hot water pipewcrk is heated by the first energy source, whereas the central heating system and/or the second hot water pipewcrk is heated by the second energy source; wherein one or both the second ports of the first and the second valves remain closed. [E 1005

54. A control unit as claimed in Claim 40, wherein the control unit is configured to control the heating system so that when the second energy source is in use, the liquid flows through the fourth return port to the second energy source and becomes heated to a pre—determined temperature; wherein the liquid then enters the first port of the second valve and exits the second valve through the second or the third port of the second valve, as determined by and controlled by the electronic control module; wherein upon exit from third port of the second valve, the liquid flows into the pipework of central heating system and/or, as the case may be, via the third valve into the second hot water pipework; wherein having passed through the central heating system, the liquid returns to the second energy source through the fifth return port and through the fourth return port and repeats the cycle through the second energy source as determined and controlled by the electronic control module; wherein having passed through the second hot water pipework, the liquid returns to the second energy source through the third return port and through the fourth return port and repeats the cycle through the second energy source as determined and controlled by the electronic control module.

55. A control unit as claimed in Claim 54, wherein the fourth pump facilitates the flow through the central heating system andlor the second hot water pipework and through the interchange pipework; and wherein the third pump facilitates the flow through the second energy source.

56. A control unit as claimed in Claim 54 or Claim 55, wherein when the first energy source is not in operation, the second port of the first valve remains closed so as to prevent heat loss due to backflow.

57. A control unit as claimed in any one of Claims 20 to 56, wherein the control unit is conﬁgured to control the heating system so that when during the operation the first energy source the temperature measured at the first energy source is below X “C, the heat provided by the first energy source is considered insufficient by the electronic control module; and the electronic control module causes the second energy source to turn on, and the second ports of the first and the second valves to close; wherein the ﬁrst energy source can be allowed to continue to operate through the first hot water pipework. 35 IE 10055

58. A control unit as claimed in any one of Claims 20 to 56, wherein the control unit is configured to control the heating system so that when temperature at the first energy source exceeds X °C, the heat supplied by the first energy source is considered sufficient by the electronic control module; and the liquid from the first energy source is directed to heat the second hot water pipework and the central heating pipework.

59. A control unit as claimed in any one of Claims 20 to 56, wherein the control unit is configured to control the heating system so that when the temperature at the first energy source is greater than X °C but less than Y °C and the temperature in a liquid storage vessel is less than X °C, the flow is diverted to the ﬁrst hot water pipework.

60. A control unit as claimed in any one of Claims 20 to 56, wherein the control unit is configured to control the heating system so that when the temperature at the first energy source is greater than X °C but the temperature at the liquid storage vessel is greater than X °C, the flow is diverted to one or more zones of the central heating pipework.

61. A control unit as claimed in any one of Claims 20 to 56, wherein the control unit is configured to control the heating system so that when the temperature at the first energy source is greater than Y °C but the temperature at the liquid storage vessel is greater than X °C, the flow is diverted to one or more zones of the central heating pipework.

62. A control unit as claimed in any one of Claims 20 to 56, wherein the control unit is configured to control the heating system so that when the temperature at the first energy source is greater than Y °C but the temperature at the liquid storage vessei is less than X °C, the flow is diverted to each of the first hot water pipework and one or more zones of the central heating pipework.

63. A control unit as claimed in any one of Claims 20 to 56, wherein the control unit is conﬁgured to control the heating system so that when the temperature at the first energy source is greater than the temperature at the third port of the second valve, and the temperature at the third port of the second valve is greater than Z °C, the second energy source is turned off and the electronic control module checks if the first energy source can provide enough heat to maintain the temperature in the second hot water pipework and in the central heating pipework. 35 lE1oo5a1 4'1

64. A control unit as claimed in any one of Claims 57 to 62, wherein X equals 65.

65. A control unit as claimed in any one of Claims 59, 61 or 62, wherein Y equals 85.

66. A control unit as claimed in Claim 63 wherein Z equals 70.

67. A control unit as claimed in Claim 5, wherein the control unit is configured for connection with a third energy source for delivering heat to one or each of the hot water pipeworks and the central heating pipework; wherein the third energy source comprises a further energy source, different from each of the first and second energy sources, such as a solar collector for heating liquid in a third hot water pipework which in turn heats liquid in a liquid storage vessel; the third energy source being controlled by the electronic controt module in such a manner that when there is a sufficient of energy availabie in the third energy source, upon receipt of an appropriate signal from a detector means of the third energy source, the electronic control module permits ﬂow in the third hot water pipework.

68. A control unit as claimed in Claim 67, wherein a fourth valve is provided for the purpose of protecting the third energy source from frost and a corresponding return pipework extending between one of the heating pipeworks of the heating system and the third energy source; upon receipt of an appropriate signal from the detector means of the third energy source indicating that frost protection is required, the electronic control module causes the fourth valve to open to permit the flow to the third energy source from a heating pipework of the heating system.

69. A control unit as claimed in Claim 14, wherein the detector means comprises programmable thermostats connected to the electronic control module.

70. A control unit as claimed in any preceding claim, wherein the electronic control module preferably comprises a programmable electronic microprocessor.

71. A control unit as claimed in Claim 5 or Claim 20, wherein the first and the second hot water pipeworks heat the liquid of the same tiquid storage vessel.

72. l A control unit as claimed in any preceding claim, wherein, the electronic control module of the control unit of the invention is also configured to control other auxiliary N1’ lE1005 system, such as mechanical heat recovery ventilation, including bypass, timer control and ventilation speed control; wherein the ventilation speed is controlled based on measurements of the moisture content of the air and the level of oxygen or carbon dioxide in the air, as communicated to the electronic control module from the relevant detector means.

73. A control unit substantially in accordance with any of the embodiments as herein described with reference to and/or as shown in the accompanying drawings. MACLACHLAN 8. DONALDSON, Applicant's Agents, 47 Merrion Square, DUBLIN 2.