GB2478976A

GB2478976A - Heating System Controller with Minimum and Maximum Temperature Control

Info

Publication number: GB2478976A
Application number: GB1005054A
Authority: GB
Inventors: Garry Richmond Stewart
Original assignee: Individual
Current assignee: Individual
Priority date: 2010-03-26
Filing date: 2010-03-26
Publication date: 2011-09-28
Anticipated expiration: 2030-03-26
Also published as: GB201005054D0; GB2478976B; WO2011117596A1

Abstract

A heating system controller 14 has a user-settable maximum temperature control element 18 and a user-settable minimum temperature control element 20. The controller also includes timer element for setting a temperature-independent activation/on period of a heating system appliance, such as a boiler. The controller also has means to cyclically deactivate/turn-off the heating system appliance during the activation period when maximum temperature set by the maximum temperature control element is reached and for cyclically reactivating the heating system appliance during the activation period when minimum temperature set by the minimum temperature control element is reached. The invention provides for reduced energy consumption 28 when compared to the conventional heating system consumption 12, by reducing the residual heating effect after boiler shutdown once the maximum temperature is achieved. The heating system boiler may have an onboard boiler controller, and the heating system controller may be integral with the onboard boiler controller.

Description

Heating-System Controller The present invention relates to a heating-system controller, a boiler having such a heating system controller, and to a method of reducing utility costs for a heating system by using such a controller.

Conventional thermostatic controllers for heating systems have a single pre-settable target temperature in any given activation period which the heating system aims to achieve before cycling off. As part of this single pre-settable target temperature, a predefined non-selectable and non-adjustable narrow tolerance band is incorporated to provide typically one or two degrees either side of the settable target temperature.

Consequently, the heating system may continue to operate in an overshoot' fashion and thus provide heat once the settable target temperature has been reached before cycling off once the upper tolerance temperature is reach. The heating system will cycle back on again during the activation period once the ambient room temperature local to the thermostat has dropped below the settable target temperature and generally by the requisite tolerance amount below the settable target temperature.

As can be seen from the graph in Figure 2, a conventional thermostatically controlled heating system thereby closely maintains the settable target temperature during the activation period, shown by the upper line referenced 10, and similarly requires significant energy input during the activation period, as shown by the lower line referenced 12.

During an activation period, the boiler is put under a long sustained and often continuous demand whilst the radiators on the central heating circuit attempt to raise a room temperature around at least the centralised thermostat to the pre-set target temperature as quickly as possible. This sustained demand along with the maintenance / overshoot facility all leads to significantly increased utility usage.

The present invention seeks to provide a solution which reduces the amount of a utility supply required for a heating system, without or substantially without impacting a heating effect perceived by a user or occupant.

According to a first aspect of the invention, there is provided a heating-system controller comprising a user-settable maximum temperature control element, a user-settable minimum temperature control element, a timer element for setting a temperature-independent activation period of a heating system, and a system controller for cyclically deactivating the heating system during the activation period when a maximum temperature set by the maximum temperature control element is reached and for cyclically reactivating the heating system during the activation period when a minimum temperature set by the minimum temperature control element is reached.

Preferable and/or optional features of the first aspect of the invention are set forth in claims 2 to 13, inclusive.

According to a second aspect of the invention, there is provided a boiler for a heating system, the boiler comprising a heating-system controller in accordance with the first aspect of the invention which is integrated therewith.

Preferably, the boiler further comprises an integrated onboard boiler controller, the heating-system controller being integral with the boiler controller.

According to a third aspect of the invention, there is provided a method of reducing utility costs for a heating system by using a heating-system controller in accordance with the first aspect of the invention, the method comprising the step of setting a maximum temperature and setting a minimum temperature so that, during a temperature-independent primary activation period, a boiler of the heating system cycles off when the maximum temperature is reached and cycles on when the minimum temperature is reached, thereby utilising the residual heating effect of the heating system to a greater extent during the off period.

Preferable and/or optional features of the third aspect of the invention are set forth in claims 18 to 20, inclusive.

The invention will now be more particularly described, by way of example only, with reference to the accompanying drawings, in which Figure 1 shows a first embodiment of a heating-system controller, in accordance with the first aspect of the invention; and Figure 2 shows a graph representing a prior art heating system usage and a heating system usage of the present invention, both in a typical domestic environment.

Refening to the drawings, there is shown a first embodiment of a heating-system controller 14 which comprises a, typically moulded plastics, housing 16 having a user-settable maximum temperature control element 18 and a user-settable minimum temperature control element 20 which is independently settable of the maximum temperature control element. Within the housing 16 is provided a timer element along with a system control element which interfaces with the timer element for outputting control signals to a boiler of the heating system.

The housing 16 may be in two parts, thereby allowing mounting to an industry standard back plate, and/or enabling piggybacking with a secondary heating-system controller as explained hereinafter.

The user-settable maximum temperature control element 18 includes a first user interface 22 on an exterior surface of the housing 16, and this first user interface 22 is a rotary knob or potentiometer allowing a user to manually set the maximum target temperature for the room. The user-settable maximum temperature control element 18 also includes a thermostatic control device, typically housed in the housing 16, for outputting a control signal to the system control element.

The user-settable minimum temperature control element 20 includes a second user interface 24 on an exterior surface of the housing 16, and this second user interface 24 is a slide switch allowing a user to manually set the number of degrees below the maximum target temperature for the room. In this case, the switch has five positions relating stepwisely to 1 through 5 degrees C. However, preferably the switch has at least three positions, and may have four or more than five positions available for selection by the user.

The second user interface 24 thus effectively allows the user to set the minimum target temperature for the room. The user-settable minimum temperature control element 20 also includes a thermostatic control device, again typically within the housing 16, for outputting a control signal to the system control element.

Although the first user interface 22 is suggested as being a rotary knob, and the second user interface 24 is suggested as being a slide switch, these interfaces may be the same.

Furthennore, the interfaces may be part of a single or separate digital interface allowing a user to programme the heating-system controller through one or more input buttons, digital display and microprocessor.

The timer element allows a user to set and selectably adjust one or more temperature-independent activation periods of the boiler of the heating system. Therefore, although not shown, the housing 16 typically includes a timer interface for setting the or each activation period for separate and/or groups of days of the week.

The system control element can be reasonably standard control circuitry which outputs a primary activation signal to the boiler on a timer activation signal from the timer element, and a primary deactivation signal to the boiler on a timer deactivation signal from the timer element. The output of signals to the boiler may be via a wired and/or wireless transmitter within the housing 16 to a similarly wired and/or wireless receiver on or at the boiler.

The heating-system controller may of course be local to the boiler, and thus may be onboard and incorporated as part thereof. In most cases, the heating-system controller will be remote, or a second unit will be provided remotely of the boiler.

As an option, the heating-system controller may also include a supplementary controller which enables a user to override the system control element and thus revert the heating-system controller back to the conventional single pre-settable target temperature with a nanow tolerance band or overshoot / undershoot configuration.

In use, the heating-system controller preferably replaces the existing or conventional thermostatic control unit for the boiler of the heating system, and interfaces with the boiler to control it from the room in which the heating-system controller is installed.

The user sets the target maximum temperature via the first user interface 22, for example, to 21 degrees C as in Figure 2 and referenced as T', and also sets the target minimum temperature via the second user interface 24, for example, to 18 degrees C. As can be understood from the graph of Figure 2, during a temperature-independent primary activation period dictated by the timer element as set by the user, the heating system is controlled to provide heat until the target maximum temperature as set by the user is reached. Following this, the boiler is deactivated during the primary activation period. The room continues to be warmed by the residual heating effect of the heating system even as it slowly cools. Once the temperature reaches the target minimum temperature as set by the user, the system control element reactivates the boiler during the primary activation period to again supply heat to the property via the heating system.

This temperature-dependent cycle repeats until the timer element outputs a temperature-independent signal to the system control element indicating the end of the primary activation period, and thus the system control element outputs a signal turning the boiler off.

As can be seen from the Figure 2 graph, the upper line referenced as 26 indicates the greater fluctuation of temperature during the primary activation period using the heating-system controller of the present invention. The lower line referenced as 28 indicates the result of cyclical temperature-deponent deactivation and reactivation during the temperature-independent primary activation period, and the significantly reduced energy consumption in comparison to the conventional heating method indicated by line 12 is clear. Although the average temperature during the primary activation period is lower than with a conventional heating arrangement, the residual heating effect of the heating system during its temperature-dependent deactivation period is such that most user's would still feel comfortable and do not notice any particular difference.

The heating-system controller can be provided as a retro-fit device, which would thus allow it to replace an existing conventional thermostatic control unit. The heating-system controller may also be provided with the boiler for a new installation, and thus may be in the form of a kit of parts.

A second embodiment of a heating-system controller, in accordance with the invention, utilises all of the features described above. However, this controller includes an interrupter element for temperature-independently periodically deactivating and reactivating the heating system during the temperature-independent primary activation period dictated by the user-settable timer element.

The interrupter element includes an interrupter control circuit, typically provided within the housing 16 of the heating-system controller, a user-settable interrupter timer, a third user interface, and an input element for receiving a boiler reactivation signal from the system control element and/or the user-settable minimum temperature control element 20.

The interrupter timer may be formed as part of the above said timer element, or may be separate. The third user interface is preferably on the heating-system controller housing 16 and allows a user to manually set an interruption activation period and an interruption deactivation period, and these may be, for example, five minutes and two minutes respectively.

Consequently, during the temperature-independent primary activation period as set by the timer element, when the user-set target minimum temperature is reached during a cyclical temperature-dependent deactivation period, the minimum temperature control element 20 outputs a signal to the system control element which in turn outputs a signal to reactivate the boiler. The signal outputted by the minimum temperature control element 20 and/or the system control element at this time is also inputted to the inten-upter control circuit via the input element. The interrupter control circuit then controls the system control element based on the user-set interrupter timer to temperature-independently deactivate and reactivate the boiler during the cyclical temperature-dependent heating phase and until the target maximum temperature set by the maximum temperature control element 18 is reached. At this point, the interrupter control circuit reverts control back to the system controller which imparts the periodic temperature-dependent deactivation of the boiler and thus the heating system during the primary activation period. As above, during the periodic or cyclical temperature-dependent deactivation, residual heating of the property continues such that the user notices little or no difference in terms of ambient room temperature.

Although, preferably, the interrupter element is integrally formed as part of the heating-system controller, the interrupter element could be a discrete unit. In this case, the housing of the heating-system controller would preferably piggyback with a housing of the interrupter element, and the input element would be an intercept input in the form of a physical connector for, preferably releasable, mating engagement with a port of the timer element and/or system control element of the heating-system controller. This thus enables the option of the interrupter element to be a retro-fittable device for a prior installation of the heating-system controller of the present invention, or provided as part of a kit for optional selection during a new installation.

Although a boiler is described above, the present invention can be applied to any heat supply device for or of a heating system. For example, wherein the heating system is a portable standalone electric radiator, convector heater, or forced air heater, the heating-system controller can be utilised therewith.

It is thus possible to provide a heating-system controller which provides a selectably-adjustable-hysteresis heating control. It is also possible to provide such a controller which additionally temperature-independently deactivates and reactivates the heating system during a cyclical or periodic temperature-based reactivation period of the primary temperature-independent activation period.

The embodiments described above are provided by way of examples only, and various other modifications will be apparent to persons skilled in the art without departing from the scope of the invention as defined by the appended claims.

Claims

Claims 1. A heating-system controller comprising a user-settable maximum temperature control element, a user-settable minimum temperature control element, a timer element for setting a temperature-independent activation period of a heating system, and a system controller for cyclically deactivating the heating system during the activation period when a maximum temperature set by the maximum temperature control element is reached and for cyclically reactivating the heating system during the activation period when a minimum temperature set by the minimum temperature control element is reached.
2. A heating-system controller as claimed in claim 1, wherein interfaces of the maximum and minimum temperature control elements are provided on a housing.
3. A heating-system controller as claimed in claim 2, wherein the housing is mountable on a standard heating-system thermostat back-plate.
4. A heating-system controller as claimed in any one of the preceding claims, wherein at least one of the maximum temperature control element and minimum temperature control element is a rotary interface, and the remaining maximum temperature control element and minimum temperature control element is a three or more position slidable switch.
5. A heating-system controller as claimed in any one of claims 1 to 3, wherein the maximum temperature control element and the minimum temperature control element utilise the same user interface.
6. A heating-system controller as claimed in any one of the preceding claims, further comprising an interrupter element for temperature-independently periodically deactivating and reactivating the heating system during the said activation period.
7. A heating-system controller as claimed in claim 6, wherein the interrupter element includes an interrupter control circuit for temperature-independently deactivating and reactivating the heating system, an interrupter timer for outputting timing signals to the interrupter control circuit for an interrupter activation period and an interrupter deactivation period, a user-interface which interfaces with the interrupter timer for a user to set the interrupter activation period and the interrupter deactivation period, and an input element for receiving a temperature-dependent heating-system activation signal and a heating-system deactivation signal from the system controller and/or the minimum temperature control element.
8. A heating-system controller as claimed in claim 7, wherein the input element is an intercept input for directly receiving the activation signal and the deactivation signal from the system controller and/or the minimum temperature control element.
9. A heating-system controller as claimed in claim 7 or claim 8, wherein the interrupter element is disengagably mountable on a or the housing having the maximum temperature control element and the minimum temperature control element.
10. A heating-system controller as claimed any one of the preceding claims, further comprising a wireless transmitter for wireless communication with a heating system.
11. A heating-system controller as claimed any one of the preceding claims, further comprising a supplementary controller for overriding the system controller deactivation and/or reactivation.
12. A heating-system controller as claimed in any one of the preceding claims, wherein the user-settable maximum temperature control element and the user-settable minimum temperature control element define a selectably adjustable hysteresis heating control.
13. A heating-system controller as claimed any one of the preceding claims, in the form of a kit of parts.
14. A heating-system controller substantially as hereinbefore described with reference to the accompanying drawings.
15. A boiler for a heating system, the boiler comprising a heating-system controller as claimed in any one of the preceding claims which is integrated therewith.
16. A boiler as claimed in claim 15, further comprising an integrated onboard boiler controller, the heating-system controller being integral with the boiler controller.
17. A method of reducing utility costs for a heating system by using a heating-system controller as claimed in any one of the preceding claims, the method comprising the step of setting a maximum temperature and setting a minimum temperature so that, during a temperature-independent primary activation period, a boiler of the heating system cycles off when the maximum temperature is reached and cycles on when the minimum temperature is reached, thereby utilising the residual heating effect of the heating system to a greater extent during the off period.
18. A method as claimed in claim 17, wherein the setting of the maximum and minimum temperatures is manual and selectably adjustable.
19. A method as claimed in claim 17 or claim 18, further comprising the step of temperature-independently cycling the heating system off and on following reactivation of the heating system after the said minimum temperature is reach and during the said primary activation phase.
20. A method as claimed in claim 19, wherein a timing of the said temperature-independent cycling is user-settable.