A HYDRAULIC UNIT

Abstract

A hydraulic unit is for use in a multi zone heating system. The hydraulic unit comprises a variable output pump; a plurality of independently controllable valves, each valve being associated with one heating zone; and at least one temperature sensor. Each heating zone receives a heated water supply from a common heat source via the pump. The heating system includes a controller comprising a processor which receives signals from the at least one temperature sensor which processes the signals in accordance with control software. Command signals are sent to the pump and the plurality of independently controllable valves, to vary the flow rate of water from the common heat source to each of the heating zones independently one to another. Remote fault diagnosis and control is also provided.

Claims

1. A multi zone heating system including a common heat source (100) therefor, a pump (55, 155, 255) and a plurality of heating zones (10), at least one heating zone has a plurality of sub-zones and further comprising a hydraulic unit (50), wherein the hydraulic unit (50) includes a plurality of independently controllable valves (86), each of the independently controllable valves is associated with a supply to each of the heating zones and is operative to supply a zone, and any sub-zone therewithin, with heated water from the common heat source (100) via the pump (55, 155, 255), the hydraulic unit (50) comprises a controller (60, 62) which operates the plurality of independently controllable valves (86) and controls an output of the pump (55, 155, 255); the hydraulic unit (50) further comprises a flow sensor (59), at least one temperature sensor (8, 58) and a processor which receives a temperature signal from the at least one temperature sensor (8, 58), associated with a heating zone (10), and a flow signal from a flow sensor (59), associated with a heating zone (10), the processor is operative to process the temperature signal and the flow signal in accordance with control software and to issue a command signal to the pump (55, 155, 255) and to at least one of the independently controllable valves to vary the flow rate of water from the common heat source to the heating zone (10) associated with the flow signal and the temperature signal, whereby the at least one independently controllable valve (86) is operable to divert heated water to a zone in response to at least one temperature signal from a temperature sensor (8, 58) associated with the at least one zone, wherein one or more sub-zones includes radiators having modulating valves (51, 52); and a controller (60, 62) comprises a processor which receives signals from the at least one temperature sensor (8, 58), flow sensor (59) or pressure differential sensor; the processor processes the signals in accordance with control software and issues command signals to the pump (55, 155, 255) and a plurality of independently controllable, modulating valves (51, 52), to vary the flow rate of water from the common heat source (100) to each of the heating zones (10) independently one to another, thereby enabling the hydraulic unit (50) to control balancing of heating of sub-zones.

2. The system according to claim 1 wherein the processor is configured to receive signals from a pair of differential pressure sensors (59a and 59b) positioned on opposing sides of the pump (55, 155, 255).

3. The system according to claim 1, further comprising a bypass between the pump (55, 155, 255) and the plurality of independently controllable valves (86).

4. The system according to claim 3, wherein the independently controllable valves (86) comprise a removable valve actuator and wherein a seat for the valve actuator is configured to removably receive a flushing assembly (510).

5. The system according to claim 1, wherein at least one temperature sensor (8, 58) is provided on a return line to the common heat source (100).

6. The system according to claim 5 wherein the variable output pump (55, 155, 255) comprises a plurality of pumps (55, 155, 255).

7. The system according to claim 5, wherein when the processor receives a demand signal from at least one heating zone it is operative to compare the demand signal with signals from the at least one temperature sensor (8, 58) to determine a required flow rate prior to issuing a command signal to the pump (55, 155, 255).

8. The system according to claim 6, wherein the hydraulic unit (50) comprises at least one variable output pump (55, 155, 255) for each heating zone.

9. The system according to claim 5 wherein at least one heating zone (10) comprises a closed heating circuit.

10. The system according to claim 1, wherein the common heat source (100) comprises at least one of: a boiler, a water heater, a hydrogen burner or a heat pump (55, 155, 255).

11. The system according to claim 1, wherein at least one of the plurality of independently controllable valves further comprises a flushing point to enable a selected zone to be tapped.

12. The system according to claim 11, wherein the system is a domestic system and wherein the plurality of heating zones (10) comprise at least one space heating loop and at least one hot water supply.

13. The system according to claim 12, wherein the hydraulic unit (50) is positioned on a return side of the common heat source (100).

14. The system according to claim 12 wherein a zone valve (51, 52) senses temperature and flow rate fluctuations, and a controller sends an error code when a fault is detected.

15. The system according to claim 12 wherein the controller has a transmitter which sends an error code to a mobile communications device, which has been modified with application specific software (APP), to perform remote control and/or remote fault detection.

16. The system according to claim 12 includes a weather compensation controller which is used to improve efficiency of the system and efficiency of the controller.

Description

DESCRIPTION OF THE DRAWINGS

[0062] FIG. 1 shows a schematic representation of a multizone heating system in accordance with an embodiment;

[0063] FIG. 2 shows a schematic representation of a hydraulic unit for use in embodiments of the invention;

[0064] FIG. 3 shows a schematic representation of an alternate hydraulic unit for use in embodiments of the invention;

[0065] FIG. 4 shows a schematic representation of a further alternate hydraulic unit for use in embodiments of the invention;

[0066] FIGS. 5A and 5B illustrate the inclusion of a flushing assembly for use in embodiments;

[0067] FIG. 6 shows an addition to control of zones, the hydraulic unit may be used to control all radiators and additional zones within dwellings;

[0068] FIG. 7 shows diagrammatically how the hydraulic unit may be retrofitted to existing buildings; and

[0069] FIG. 8 shows an overall view of a system fitted with a controller which receives data from auto radiator balancing valves and thermostats.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS OF THE INVENTION

[0070] A heating system 1 in accordance with an embodiment is illustrated schematically in FIG. 1. The heating system may be a domestic hot water and space heating system and includes two heating zones 10 and 20 which are each closed loops that receive hot water from a heater/boiler 100.

[0071] The heating system has an out flow 2 and a return 3 to the boiler 100. The flow splits into the separate circuits 10 and 20 of the heating zones which each have a respective inlet 11, 21 and return 12, 22. In the illustrated embodiment the first circuit/zone 10 is a hot water loop and includes a cylinder 15 which may have a hot water outlet 16.

[0072] The second circuit/zone 20 is a space heating circuit and includes at least one radiator 25 (or typically a plurality of radiators which may be arranged in a number of sub-zones, for example in parallel or series). A hydraulic unit 50 in accordance with embodiments is provided at the return 3 to the boiler 100 and receives the return flow lines 12, 22 from both heating zones 20, 10. A controller 60 is in communication with the hydraulic unit 50 and boiler 100. The hydraulic unit comprises two modulating zone valves, each zone valve has its own temperature sensor which can be in or next to the valve. The modulating zone valve also comprises a flow sensing device which can be in or next to the valve. Therefore, the controller 60 is also in communication with the temperature sensors and flow sensors within the hydraulic unit. The hydraulic unit also consists of a modulating pump with a flow sensing device, the controller is also connected to this flow sensing device/s and the modulating pump. The controller 60 may be connected to additional temperature sensors on the system external to the hydraulic unit.

[0073] In this way a second, optionally smaller boiler, removes the additional load of having to heat two heating zones from a larger boiler. This second boiler effectively provides a completely separate system. Again it is appreciated that the hydraulic unit may be adapted to oversee two space heating zones. Optionally additional hydraulic units may be provided where a larger boiler heats two or more heating zones.

[0074] This enables one or more space heating loops or at least one hot water supplies or at least one space heating loop and one hot water supply to be serviced at the same time.

[0075] In this configuration a smaller boiler is able to heat two heating zones and a much larger boiler which is separate and may for example heat a swimming pool heat exchanger.

[0076] Optionally, the heating system may be fitted with a bypass 80 which may for example provide a direct return route between the output 2 and the return 3. The bypass may divert flow past the hydraulic unit 50 for example to protect the pump against overpressure damage.

[0077] However, as the system has an independently controlled hydraulic unit via a controller, it can be set to allow the hydraulic unit to allow flow through the valves, via the modulating pump, which were in demand while the heat source is shut down. Therefore temperature and pressure is reduced, then the entire system shuts off once a pre-determined temperature is met. This setting may also be used in some systems as a free comfort mode.

[0078] This is used to pre heat a secondary heat exchanger that may hold stored water. This allows the time taken for hot water to reach the faucet to shorten. In most cases a heat source would have to use extra energy to do this in its own time but while the spare heat is circulating to cool itself down unnecessarily, it would seem wise to use this energy to preheat a secondary heat exchanger. With all this said, all systems, unless specified to, would not need a bypass when fitted with the hydraulic unit configuration.

[0079] The configuration of the hydraulic unit 50 is shown in FIG. 2. The hydraulic unit 50 includes an independently controllable modulating valve 51, 52 for each of the respective zones 10, 20. Valve 51 is in communication with the return line 12 of the first zone 10 and valve 52 is in communication with the return line 22 of the second zone 20.

[0080] It will be appreciated that further valves may be provided for additional zones as required. The hydraulic unit further comprises a variable output pump 55 which receives flow from the valves 51, 52 and feeds an output line 56 to supply the return line 3 of the boiler 100.

[0081] Thus, flow through the heating zones 10, 20 is via the pump 55. In the configuration of FIG. 2, the output lines 53a, 53b from the valves 51, 52 are fed through a common manifold 54 to the pump 55. Temperature sensors may be provided in the hydraulic unit 50, either within the modulating zone valves or further down the output lines 53a, 53b. for example individual sensors 58a and 58b on the output lines or a common temperature sensor 58 on the combined flow in the manifold 54.

[0082] Alternatively or additionally, the hydraulic unit 50 may use temperature sensors 8, 8 located on the return lines external to the hydraulic unit 50. Flow sensors may also be provided in the hydraulic unit 50. For example, a pair of differential pressure sensors 59a and 59b can be provided on opposing sides of the pump 55. Also there are provided flow sensing devices located on either modulating zone valves 51, 52 or further down line, in an output lines 53c, 53d. The valves 51, 52, sensors 53, 58, 59, and pump 55 are all connected to the controller 60.

[0083] In some embodiments the pressure requirements of the system may necessitate the provision of a hydraulic unit 150, as shown in FIG. 3, having a plurality of pumps 155. The overall configuration of such an embodiment may be generally consistent with a single pump embodiment (and similar components are indicated with the same reference numerals prefixed with a 1). As may be noted in this embodiment the pumps 155a, 155b are simply arranged in parallel but operate in the same manner as the single pump embodiment of FIG. 2.

[0084] Alternatively, as shown in FIG. 4 in some embodiments dedicated pumps 255a and 255b may be provided each associated with one of the zones. As such the hydraulic unit 250 of this embodiment includes for each zone: an independent input 212/222, a valve 251/252 and a pump 255a/255b. Depending upon the system configuration the hydraulic unit 250 could be provided with separate return lines 203a and 203b for each zone or could have a single combined return line 203. As previously stated, a system may benefit from separate return lines 203a and 203b when two separate heat sources are used in two separate systems.

[0085] Conveniently, the independent control valves 51/52, 151/152, 251/252 may also be used as flushing points for the heating system. As shown in FIG. 5A the body of the valves 501 may include a threaded bore 502 sealed with an O-ring 503. In normal operation this threaded bore can receive the valve actuator. For system maintenance the valve actuator may be removed and a flushing valve 510 may be inserted into the valve body 501. The flushing valve 510 has a valve body including a threaded collar 512 for engaging the threaded bore 502 and a flow diverter 514.

[0086] The flow diverter passes the system flow through a filter 515 which may for example be a magnetic filter. The filtering function is show schematically in FIG. 5B with the flushing valve 510 diverting incoming flow (represented by arrow I) through the filter 515 and returning it to the system (in the direction of output arrow 0).

[0087] Some of the advantages of embodiments of the invention in use will now be described in further detail.

[0088] Embodiments enable the controller 60 to actively balance and/or purge the heating system 1 by the controller using the independent valves 51/52, 151/152, 251/252 and the speed of the pump(s) 55, 155, 255 to provide an optimised flow through each zone 10, 20 across a variety of operational situations. The controller may maximise efficiency by both ensure that the energy (i.e. the flow rate and heat) supplied to each zone closely matches that required and by ensuring that return flows to the heater 100 are at cool temperatures (which allows the heater itself to work more efficiently).

[0089] For example, in a space heating zone there may typically be a number of radiators 25 and each may be fitted with an individual thermostatic radiator valve. These such thermostatic valves close off a radiator once the local ambient temperature is reached. In embodiments of the invention, the controller can respond to this decreased demand by reducing the output of the pump so that only the amount of energy required by the zone is supplied rather than the pressure in the system increasing if a constant pump were used. Likewise, the controller could use the variable output pump to respond by increasing the pump speed if a radiator subsequently activated. In parallel the controller can also further adjust the flow in each zone (for example the relative flow in the zones) by controlling the extent to which the independent control valves of the hydraulic unit are opened.

[0090] In use, a user demand signal is sent to the heat source 100 (for example from the user interface 62 or by the use of a hot water outlet) causing the controller 60 to activate the hydraulic unit 50. The controller 60 activates or adjusts valve(s) 51/52, 151/152, 251/252 associated with the zone and activates the variable output pump 55, 155, 255. Using data from the return temperature thermostat(s) 8, 58 and the flow sensing device 53c, 53d the controller 60 instructs the pump to run at a specific flow rate to suit user demand.

[0091] For example, hot water is demanded (from zone 10) and the primary heat source 100 is cold, the controller would understand this via flow 59 and temperature sensors 8, 58 and run the pump 55 at full rate. Once hot water is up to temperature and the return temperature has balanced out the primary heat source 100 may modulate lower than full rate, at this stage the pump 55 may also do so to save on electrical energy. This is because it would be seen as a top up of energy once a predefined temperature has been met. Or if a specific cold-water inlet flow rate is lower than the appliance is able to heat up and would not need to use full input to achieve the desired hot water flow rate. In some embodiments this may achieve low return temperatures back to primary heat sources which can produce a higher efficiency of a primary heat source.

[0092] Domestic hot water (zone 10) demand would typically take priority until a predetermined set temperature is an achieved. Once this predetermined set temperature is achieved, a user would be able to ask for space heating (from zone 20) as well as hot water generation (typically the set temperature may take only a few seconds to achieve). While the primary heat source 100, hot water zone valve 51 and modulation pump 55 are running for hot water generation, the integral dual zone valve 52 will open up to a certain degree and a return temperature is monitored within the valve, for example by temperature sensor 58b.

[0093] As the controller 60 understands that a secondary zone 20 is opening and temperatures are decreasing it causes the primary heat source 100 to modulate to a higher rate of heat transfer. At the same time, the controller causes the pump 55 to increase pump speed to suit flow rate needed to accommodate more water passing through the hydraulic unit. Again, as return temperatures start to rise or stabilise, the heating zone valve 52 opens until a full flow is achieved and the modulating pump 55 then commences pumping and sets its pump speed to the desired speed needed for the volume of water being pumped around the system 1.

[0094] As noted above, if a space heating zone 20 incorporates radiators 25 with thermostatic radiator valves, they may shut down flow to each individual radiator while an overall room thermostat is asking for heat demand. In traditional systems the manufacture would generally specify that a radiator with permanent lock shield valves or a permanent bypass be fitted. In a system in accordance with embodiments the flow sensor 59 within the pump 55 and temperature sensor(s) 58/8 ensure that the controller 60 can accurately sense when a system is reaching zero flow rate and reduce the pump speed until a maximum pressure and temperature is sensed. At that point, the controller shuts down the primary heat source 100 and continue to run the hydraulic unit 50 of until a predetermined temperature and pressure is met then they too shut down shortly after.

[0095] In the case of a sudden flow shut off, all zones 10, 20 may automatically open up to dump any latent heat once the primary heat source 100 has shut down.

[0096] Advantageously, embodiments of the invention may enable the controlled to prevent confusion between an actual fault with a system and human error since the controller 60 may use the temperature signals form the hydraulic unit in conjunction with the flow sensor signals. For example, the controller can be instructed to use the temperature and flow signals from the hydraulic unit to shut off the primary heat source if a maximum pressure/minimum flow rate is exceeded and/or temperature differential between both zone temperature stats and primary heat source flow/return temperature stats exceed a predetermined temperature difference.

[0097] For example, if a thermostatic radiator valves fails or is set incorrectly the space heating may be determined via a room thermostat rather than the thermostatic radiator valve. This can result in minimal to no flow rate on initial start-up as all thermostatic radiator valves are shut off. In embodiments of the invention the hydraulic unit signals would enable the controller to identify this issue. The controller may, therefore, shut the primary heat source down and send an error code, saving many components including the primary heat source from additional damage.

[0098] Another problem maybe blockages within a system, again the hydraulic unit would enable the controller to shut down before any more damaged occurred and an engineer could fix the problem and restart the unit once again.

[0099] Another advantage of embodiment is that as either zone is completely separate (and in some embodiments so is the pump) it could send separate fault codes for each individual zones. For example, a valve may be shut off leading to a cylinder and the pump and zone valve sense temperature and flow rate fluctuations, sends an error code but because the other zone is working well, the primary heat source is kept working in the meantime. An engineer can visit and solve the problem without having to shut down the entire system.

[0100] When a hot water zone 10 is being used to indirectly heat a stored water cylinder 15 embodiments of the invention may further increase efficiency and reliability of a system by enabling a predetermined set temperature to be reached before needing to pump overrun. Once the controller of the hydraulic unit has communicated with the primary heat source and the cylinder thermostat, it is able to calculate a time period between shutting off the primary heat source and reaching the cylinder thermostat set temperature to allow the primary heat source to cool enough before shutting off the zone and pump without needing a bypass.

[0101] FIG. 6 shows how, in addition to controlling zones, the hydraulic unit may be used to control all radiators and additional zones within dwellings. It may comprise a one or more automatically controlled radiator balancing valves with wireless control 86a. It may comprise one or more thermostatic radiator valves which are also wirelessly controlled 86c.

[0102] It may comprise 1 or more automatically controlled balancing valves with wireless control 86b, situated on a return pipe leading from a stored water unit such as a vented cylinder.

[0103] It may comprise a user controller 62, to examine all data from the auto radiator balancing valves 86a, auto balancing valves 86b, thermostatic radiator valves 86c and the main modulating zone valve 51 returning to the heat source from the dwelling via wireless signals.

[0104] This would then send the data to the main controller within the plant room 60, wirelessly, which would then instruct the modulating pump 55 within the hydraulic unit 50 to set a desired flow rate and run the heat source at the same time.

[0105] In this way, complete control over the entire system down to the smallest circuit can be achieved and no extra energy would be wasted.

[0106] It should be said that wirelessly controlled thermostatic radiator valves are well known necessity to this schematic when relaying information back to the control unit to state whether a radiator is shutting down due to ambient temperature or there is a fault within the system.

[0107] FIG. 7 shows how the hydraulic unit may be retrofitted to existing buildings. In this way, the modulating, independently controlled zone valves 51, may be fitted on return pipe 75, leading towards the hydraulic unit 50 and heat source 100. The modulating independently controlled zone valves send data via their temperature and flow sensors to the user controller 62 for that dwelling that it is situated. If demand is needed, that user controller 62 then sends a signal to the main controller 60 within the plant room. The main controller 60 sends a signal to the modulating pump 55 within the hydraulic unit 50 to set a desired flow rate and run the heat source at the same time.

[0108] Temperature sensors may be located on the flow, as well as on the return pipework, which is connected to a zone or a sub-zone. The system therefore has the ability to reduce or increase a temperature differential (delta T) across zones and/or sub-zones, so that exact temperatures can be used to obtain different output temperatures from a heat source such as a boiler, for example. This precise control is achieved by reducing or increasing flow rate across a zone and/or a sub-zone, then monitoring the temperature differential until a correct temperature output is achieved, so as to heat the zone and/or sub-zone which is being supplied.

[0109] Optionally a weather compensation controller may be used to improve efficiency of the system and efficiency of the controller. Weather compensation control means maintain internal temperatures by varying the flow temperature from the heat source relative to the measured outside temperature. When included with the system a weather compensation controller enables the controller to compensate within each zone and/or sub-zone rather than throughout an entire dwelling which was previously the case.

[0110] In the past weather compensators have only been able to govern effectively the entire dwelling and reduce temperature from a heat source but have never been able to oversee different temperatures to radiators in different rooms, for example which may be located on a northern side of a building, compared with those rooms which face the sun on a southern side of a building, because the heat source or boiler was only capable of outputting water at a given temperature.

[0111] This problem is now overcome because individual flow rates can be controlled precisely and therefore temperature differentials between zones or sub-zones can be managed.

[0112] For example, a radiator with a mean temperature of 50 C. and a design temperature of an ideal room temperature of 21 C. provides a 1 kW. If the mean temperature is reduced to 35 C. then the radiator output falls to 600 W. A weather compensator, which provides a signal to the controller, enables this to occur, even when the temperature difference between inside a dwelling and outside a dwelling are very close, for example when an external temperature is 18 C. and there is a 21 C. demand from a thermostat within a dwelling.

[0113] Another benefit of using temperature sensors located on the flow as well as return pipework in a zone or sub zone is that heat losses can be quickly and accurately identified throughout all areas of the system. For example if a 65 C. output is provided by a heat source and water arrives at 30 C., at a correct flow rate, a substantial amount of heat has been lost heat which might prompt investigation to be made, for example to locate unlagged pipework.

[0114] Such a configuration may also be used when reduced pipework is needed within a building as each wirelessly controlled zone can be fitted into a separate dwelling on the return pipework returning back to the hydraulic unit 50 and heat source 100.

[0115] FIG. 8 shows an overall view of a system fitted with a controller which receives data from auto radiator balancing valves and thermostats. FIG. 8 shows automatically controlled radiator balancing valves with wireless control 86a and one or more thermostatic radiator valves 86c which are also wirelessly controlled via, for example using Bluetooth (RTM) wireless protocol, communication devices. Other types of short range wireless control devices, such as Zigbee (RTM) wireless protocol devices may also be deployed.

[0116] The system shown in FIG. 8 has automatically controlled balancing valves 86b operating under wireless control. These balancing valves are shown on a return pipe leading from a stored water unit, such as a vented cylinder.

[0117] Further variation may be made to the hydraulic assembly so as configure it to be suitable for use with a plurality of zones. Such a configuration may comprise an odd number of zones. For example if there are nine zones, one zone is potentially wasted because ideally the system optimises an even number of zones.

[0118] The invention can be enabled to suit any other heat source available, increasing efficiency, such as for example hydrogen burners and heat pumps.

[0119] If required, two or more hearting zones require at least two valves which communicate one with one another so as to modify and correct flow temperatures.

[0120] Although the invention has been described above with reference to preferred embodiments, it will be appreciated that various changes or modification may be made without departing from the scope of the invention as defined in the appended claims.

[0121] For example, whilst the Figures above represent the hydraulic unit in a single location, it will be appreciated that the valves and pump may be spaced apart by suitable piping if this is more appropriate for a particular heating system. This may for example be necessary where a hydraulic unit is retrofitted to an existing heating system with existing spacing constraints.