GB2547542A

GB2547542A - Boiler air temperature compensation

Info

Publication number: GB2547542A
Application number: GB1700483.9A
Authority: GB
Inventors: Dieterman John; Horne Phil
Original assignee: BDR Thermea Group BV
Current assignee: BDR Thermea Group BV
Priority date: 2017-01-11
Filing date: 2017-01-11
Publication date: 2017-08-23
Anticipated expiration: 2037-01-11
Also published as: GB2547542B; GB201700483D0

Abstract

The weather compensation system comprises a weather compensation active component, ideally a thermistor 1, to measure the temperature of outside air drawn into an air intake 13 of a balanced flue 10 for combustion in a boiler 9. The component is connected to the balanced flue and may be located at least partially inside the air intake. The component is electrically connected to the boiler and the boiler adjusts a target temperature of water heated by the boiler based upon the measured outside air temperature. Location of the component/thermistor within the air intake may shelter the component from direct sunlight. A balanced flue, method of adjusting a set point temperature of water from a boiler, method of installing a weather compensation system, and method of installing a boiler are also claimed.

Description

BOILER AIR TEMPERATURE COMPENSATION

Technical Field

The present disclosure relates to use of weather compensation in boiler control and more particularly to a boiler air temperature compensation system.

Background

Use of weather compensation for heating controls is desirable since it improves the efficiency of heating systems and reduces costs for the consumer. Traditionally a boiler or heat source may be controlled based on the feedback response of a thermostat located inside a building. This typically leads to inefficient cycling of the boiler and the system will often overheat the interior of the building.

Weather compensation systems typically use outdoor sensors mounted on external walls to determine the outdoor temperature. The system adjusts the central heating radiator flow temperature depending on changes in outdoor temperature. As the outdoor temperature cools, the system will gradually work harder to produce more heat. The system runs more consistently and more efficiently since boiler switching cycles are minimised. Comfort within the building is also improved since a more constant temperature is maintained within.

Existing weather compensation systems typically utilise an outdoor sensor that is often costly and expensive to fit especially for installations in tall buildings, such as apartment blocks. Furthermore the sensor must be located on a north-facing wall (or equivalent depending on geographic location) in order to avoid direct radiation from the sun. The sensors may be unsightly and impossible to fit if a property such as an apartment or terraced house does not have a north-facing wall.

It is an object of this invention to provide an improved weather compensation system and method.

Summary

In one aspect the present invention provides a weather compensation system for use with a boiler.

Accordingly, there is provided a weather compensation system for use with a boiler comprising a weather compensation active component that measures an outside air temperature of air that is drawn into an air intake of a balanced flue for combustion in the boiler. The weather compensation active component is connected to the balanced flue, located proximal to an air inlet of the air intake, and is electrically connected to a boiler control unit. The boiler is configured to heat water to a set point temperature and the boiler control unit adjusts the set point temperature based on the measured outside air temperature value.

It will be appreciated that, in general, the temperature of air within the boiler will not itself be the same as, or directly related to the outdoor air temperature, especially with boilers that operate with a balanced flue. However, the present inventors have determined that placement of the weather compensation active component proximal to the air inlet of the air intake allows for the outside air temperature to be measured accurately. Furthermore, since the temperature is determined by the weather compensation active component that is connected to the balanced flue, there is no requirement for a separate external sensor to be mounted on an exterior wall. All the problems associated with the use of an outdoor sensor as described above are therefore mitigated.

The weather compensation active component may be situated at a position inside, outside, or partially inside the intake.

It may be advantageous for the weather compensation active component to be located within the air intake as it is not subject to interference from external elements such as other domestic heat sources or solar radiation. It is convenient for new boilers to be provided that incorporate a weather compensation active component since the end user will not be burdened with the requirements and cost of fitting an external sensor as discussed above. It is also similarly convenient to retrofit existing boilers with a weather compensation active component. The weather compensation active component may be a simple cheap device such as a thermistor, and therefore the cost of implementing the system or the added cost of incorporating it into a new boiler is minimal.

The weather compensation active component may intersect with the air inlet. This positioning is advantageous since it is ensured that the component is exposed to outside air flowing into the air intake of the balanced flue. This improves the possibility of the component to obtain an accurate measurement of the outside air temperature.

In order to further ensure that an accurate measurement of the outside air temperature is taken, the weather compensation active component may be substantially within a flow of air into the air inlet. Since air from outside is flowing into the air inlet, the risk of the measurement being affected by heat sources such as exhaust gases or other domestic heat sources is minimised. Furthermore, the transmission by convection of any heat generated by the boiler and detection of this heat by the weather compensation active component is minimised.

The weather compensation active component may be located in a sheltered location that does not receive direct sunlight. This is advantageous in ensuring that the component is always in the shade and would therefore not be adversely affected by solar radiation whichever side wall the balanced flue is connected to. Furthermore there is advantageously no requirement for sensors to be placed on walls that face a particular direction away from sunlight.

The weather compensation active component may be connected to a boiler control unit by a cable that runs through the balanced flue, and preferably runs through the air intake. This has the advantage of simplifying the installation procedure of the weather compensation system thereby reducing costs incurred and time taken during installation. An installer does not need to consider drilling holes in walls or performing other substantial work in order to place the cable as would usually be the case where a traditional external temperature sensor is fitted.

The weather compensation active component may be detachably clipped to the balanced flue, thereby further simplifying the installation process and allowing the component to be easily replaced.

The weather compensation active component may be a thermistor, integrated circuit temperature sensor, thermocouple, resistance temperature detector, negative/positive temperature coefficient thermistor, or any other form of electrical temperature sensor.

In a second aspect, the present invention provides a balanced flue for connection to a boiler comprising a weather compensation active component that measures an outside air temperature, an air intake channel for supplying outside air to a combustion chamber of the boiler, and a flue gas channel for exhausting flue gas from the combustion chamber. The weather compensation active component is located proximal to an air inlet of the air intake channel.

The weather compensation active component may be located inside, outside, or partially inside of the air intake.

The weather compensation active component may intersect with the air inlet.

The weather compensation active component may be connected to a boiler control unit by a cable that runs through the balanced flue, and preferably runs through the air intake.

The weather compensation active component may be substantially within a flow of air into the air intake.

The weather compensation active component may be located in a sheltered location that does not receive direct sunlight.

The weather compensation active component may be detachably clipped to the balanced flue.

Hereinafter, the terms “horizontal” and “vertical” may be interpreted as being substantially horizontal or vertical with respect to the ground. A portion of the balanced flue comprising portions of the air intake channel and flue gas channel may be situated horizontally and said channels may be horizontal. A portion of the balanced flue comprising portions of the air intake channel and flue gas channel may be situated vertically and said channels may be vertical.

It is advantageous for portions of the balanced flue to be horizontal or vertical since the installation procedure is further simplified. For example, an installer may push or slot exterior portions of the balanced flue (i.e. those that are to be located outside of a building) through a wall from inside a building. The installation procedure is especially simplified where the balanced flue is to be situated so that it is not accessible from ground level. It may be advantageous for the length of exterior portions to be sufficient so that flue gases emitted from the end of the balanced flue are not discharged undesirably such as into a window or into the face of a person. A Chinaman’s hat flue terminal or cowl may be placed at an end portion of the balanced flue. The weather compensation active component may be located in the shadow of the Chinaman’s hat flue terminal or cowl. In this location the component advantageously is not adversely affected by heat caused by direct sunlight. The Chinaman’s hat flue terminal or cowl may further prevent weather damage to the weather compensation active component, for example from rain.

In a third aspect, the present invention provides a method of adjusting the set point temperature of water from a boiler.

The method may comprise the steps of:

Using a weather compensation active component to measure an outside air temperature of air for combustion drawn into the boiler via an air inlet of a balanced flue. The weather compensation active component being located proximal to the air inlet and electrically communicating with a boiler control unit. Configuring the boiler to heat water to a set point temperature. - Adjusting the set point temperature based on the measured outside temperature.

In a fourth aspect, the present invention provides a method of installing a weather compensation system for use with a boiler comprising the steps of:

Placing a weather compensation active component proximal to the air inlet of a balanced flue and outside a path of flue exhaust gas; - Slotting the balanced flue for connection to a boiler through a hole in an exterior wall, so that the air inlet and the weather compensation active component protrude outside the wall. A cable may be threaded from the weather compensation active component for connection to a boiler control unit through the balanced flue, and preferably through an air intake of the balanced flue. This step may take place before the step of slotting the balanced flue through the wall. It is advantageous for the installer to not have to perform the step of threading the cable through the balanced flue when on site since this action will take time and increase the complexity of the installation. Furthermore, the installer does not have to go outside which is especially beneficial when performing an installation in flats on upper floors. It is also advantageous for the cable to be threaded through an air intake of the balanced flue since the effect of heat from hot flue exhaust gas on the cable is reduced.

The weather compensation active component may be detachably clipped to a portion of the balanced flue.

The balanced flue may be slotted from the inside of a building. There is advantageously no requirement for an installer to have access to the exterior location of the balanced flue. Such access may be difficult to achieve where, for example, the building is multi-storey.

In a fifth aspect, the present invention provides a method of installing a boiler for use with a weather compensation system comprising the steps of: slotting a balanced flue comprising a weather compensation active component through a hole in an exterior wall; connecting said balanced flue to the boiler. A cable may be threaded from the weather compensation active component for connection to a boiler control unit through the balanced flue, and preferably through an air intake of the balanced flue. This step may take place before the step of slotting the balanced flue through the wall. As discussed above, it is advantageous for an installer to not be required to perform the step of threading on site.

The weather compensation active component may be attached to a portion of the balanced flue proximal to an air inlet of the balanced flue and outside a path of flue exhaust gas.

The balanced flue may be slotted from the inside of a building.

Advantages of particular aspects may also apply to other aspects of the invention.

Brief Description of Drawings

Figure 1 shows a schematic of a boiler and relevant components of a weather compensation system in accordance with an embodiment of the present invention.

Figure 2 shows a side view of the underside of an end portion of a balanced flue in accordance with an embodiment of the present invention.

Figure 3 shows a view of an end portion of a balanced flue in accordance with an embodiment of the present invention.

Figure 4 shows a schematic view of a placement of a balanced flue on a multi-storey building in accordance with an embodiment of the present invention.

Figure 5 shows a schematic view of a placement of a balanced flue on a house in accordance with an embodiment of the present invention.

Detailed Description

With reference to Figure 1, a weather compensation active component (hereinafter referred to as the “component”) 1 is mounted at a position proximal to a balanced flue air inlet 2. The component is, for example, a thermistor. In operation, outside air will flow through a balanced flue air intake 13 via the air inlet 2. The temperature of this outside air flow is measured by the component 1. This temperature is hereinafter referred to as the outside air temperature. A boiler 9 contains a gas burner 8 that is supplied by a fuel gas (not shown). The outside air flow provides oxygen to enable combustion at the gas burner. The exhaust gas from this combustion creates a hot flue gas flow. The flue gas flows down flue gas channel 14 and exits the balanced flue via flue gas outlet 3 (as shown by arrow 12b).

Balanced flue 10 passes through an exterior wall 15 in order to access fresh outside air from outside a building and to enable the flue gas flow to be exhausted away from the building or persons.

It should be noted that the component 1 may be situated at any suitable point for measuring the outside air temperature. Component 1 may be located at any point within air intake passage 13 where the temperature of the outside air flow is substantially the same as the outside air temperature. It is generally known that the flue gas flow is hot. The inventors have found that the hot flue gas flow exiting the flue gas outlet 3 does have a substantial effect on the temperature measured at positions proximal to the air inlet 2.

In the embodiment shown, the component 1 is located on a downward-facing portion of the balanced flue (i.e underneath the flue gas outlet). This ensures that the component is always in the shade and would not be affected by/exposed to solar radiation whichever wall the balanced flue protrudes from.

Arrow 13a shows the direction of water flow into the boiler 9 from a central heating system (not shown) and arrow 13b shows the direction of water flow out of the boiler 9 and into the central heating system (not shown). Such flow may be referred to as the central heating radiator flow. There is a control system 6 that controls the firing of the burner 8. The control system 8 is connected to the component 1 by a cable 11 that runs through air intake 13.

The outside air temperature that has been measured is used as an input to the control system 6 to determine an ideal set point water temperature setting using established principles of weather compensation. There may be a further input (not shown) for human input of a desired indoor temperature. The burner is accordingly controlled so that the ideal set point water temperature is attained in order that that the desired indoor temperature is achieved using weather compensation principles.

With reference to Figures 2 and 3 there is shown an end portion of a balanced flue. Where applicable the reference numerals refer to the same features as described with respect to Figure 1. The component 1 is clipped to the balanced flue using clip 4. The component may be detached in the event that it needs to be replaced.

With reference to Figure 4 there is shown a multi-storey building 401 and horizontal external portion of balanced flue 10. The balanced flue 10 has been slotted through a wall of the building from the inside of the building 401. The balanced flue incorporates features as described in the previous Figures, and the associated central heating system is therefore enabled for weather compensation without requiring any further external sensors or cabling. The component 1 is an under-side or downward-facing portion (a sheltered location) of the balanced flue 10 and is therefore not exposed to direct sunlight from the sun 402.

With reference to Figure 5 there is shown a house 501 and a vertical portion of balanced flue 10. The flue gases are emitted from a top portion of the balanced flue and therefore there is a lesser risk that persons on the ground will be affected by the flue gas flow. The balanced flue 10 incorporates features as described in the previous Figures, and the associated central heating system is therefore enabled for weather compensation without requiring any further external sensors or cabling. Chinaman’s hat 502 is situated on top of an end portion of the balanced flue 10. Component 1 is situated in the shadow of the Chinaman’s hat 502 and is therefore not exposed to direct sunlight from the sun 402.

In further embodiments, the invention relates to a method of installing a boiler. During installation, an installer slots balanced flue 10 through an exterior wall 15 and connects it to the boiler 9. The balanced flue 10 comprises a weather compensation active component 1 that is positioned proximal to an air inlet of the balanced flue and outside a path of flue exhaust gas. The installer may further thread a cable 11 from the weather compensation active component 1 to the boiler control unit 6 through the balanced flue 10. The cable 11 is preferably threaded through the air intake 13 of the balanced flue 10. Alternatively, the cable 11 is already threaded through the balanced flue 10 before it is slotted through the wall and the installer is not required to perform the action of threading. For example the balanced flue 10 may be supplied to the installer with the cable 11 and component 1 already in place and the installer merely connects one end of the cable 11 to the boiler control unit 6. Boilers according to the present invention that incorporate weather compensation therefore do not require any further substantial installation work compared to existing boilers that do not incorporate weather compensation. The weather compensation active component 1 may be detachably clipped to the balanced flue using a clip 4.

Claims

Claims:

1. A weather compensation system for use with a boiler comprising: a weather compensation active component that measures an outside air temperature of air that is drawn into an air intake of a balanced flue for combustion in the boiler, wherein, said weather compensation active component is connected to the balanced flue, located proximal to an air inlet of the air intake, and is electrically connected to a boiler control unit; the boiler is configured to heat water to a set point temperature; and the boiler control unit adjusts the set point temperature based on the measured outside air temperature value.

2. The weather compensation system of claim 1 wherein the weather compensation active component is located inside, outside, or partially inside of the air intake.

3. The weather compensation system of claim 1 or 2 wherein the weather compensation active component intersects with the air inlet.

4. The weather compensation system of any preceding claim wherein the weather compensation active component is substantially within a flow of air into the air inlet.

5. The weather compensation system of any preceding claim wherein the weather compensation active component is located in a sheltered location that does not receive direct sunlight.

6. The weather compensation system of any preceding claim wherein the weather compensation active component is connected to a boiler control unit by a cable that runs through the balanced flue, and preferably runs through the air intake.

7. The weather compensation system of any preceding claim wherein the weather compensation active component is detachably clipped to the balanced flue.

8. The weather compensation system of any preceding claim wherein the weather compensation active component is one of a thermistor, resistor, integrated circuit temperature sensor, thermocouple, resistance temperature detector, negative/positive temperature coefficient thermistor, or any other form of electrical sensor.

9. A balanced flue for connection to a boiler comprising: a weather compensation active component that measures an outside air temperature; an air intake channel for supplying outside air to a combustion chamber of the boiler; a flue gas channel for exhausting flue gas from the combustion chamber; wherein, the weather compensation active component is located proximal to an air inlet of the air intake channel.

10. The balanced flue of claim 9 wherein the weather compensation active component is located inside, outside, or partially inside of the air intake.

11. The balanced flue of claim 9 or 10 wherein the weather compensation active component intersects with the air inlet.

12. The balanced flue of any of claims 9 to 11 wherein the weather compensation active component is substantially within a flow of air into the air intake.

13. The weather compensation system of claims 9 to 12 wherein the weather compensation active component is located in a sheltered location that does not receive direct sunlight.

14. The balanced flue of any of claims 9 to 13 wherein the weather compensation active component is connected to a boiler control unit by a cable that runs through the balanced flue, and preferably runs through the air intake.

15. The balanced flue of any of claims 9 to 14 wherein the weather compensation active component is detachably clipped to the balanced flue.

16. The balanced flue of any of claims 9 to 15 wherein a portion of the balanced flue comprising portions of the air intake channel and flue gas channel are situated horizontally and said channel portions are horizontal.

17. The balanced flue of any of claims 9 to 16 wherein a portion of the balanced flue comprising portions of the air intake channel and flue gas channel are situated vertically and said channel portions are vertical.

18. The balanced flue of any of claims 9 to 17 further comprising a Chinaman’s hat flue terminal placed at an end portion of the balanced flue.

19. The balanced flue of claim 18 wherein the weather compensation active component is located in a shadow of the Chinaman’s hat flue terminal.

20. A method of adjusting the set point temperature of water from a boiler comprising the steps of: using a weather compensation active component to measure an outside air temperature of air for combustion drawn into the boiler via an air intake of a balanced flue; said weather compensation active component being located proximal to the air inlet and electrically communicating with a boiler control unit; configuring the boiler to heat water to a set point temperature; and adjusting the set point temperature based on the measured outside temperature.

21. A method of installing a weather compensation system for use with a boiler comprising the steps of: placing a weather compensation active component proximal to the air inlet of a balanced flue and outside a path of flue exhaust gas; slotting the balanced flue for connection to a boiler through a hole in an exterior wall, so that the air inlet and the weather compensation active component protrude outside the wall.

22. The method of claim 21 further comprising the step of threading a cable from the weather compensation active component for connection to a boiler control unit through the balanced flue, and preferably through an air intake of the balanced flue, wherein this step takes place before the step of slotting the balanced flue through the wall.

23. The method of claim 21 or 22 further comprising the step of detachably clipping the weather compensation active component to a portion of the balanced flue.

24. The method of any of claims 21 to 23 wherein the slotting of the balanced flue is done from the inside of a building.

25. A method of installing a boiler for use with a weather compensation system comprising the steps of: slotting a balanced flue comprising a weather compensation active component through a hole in an exterior wall; connecting said balanced flue to the boiler.

26. The method of claim 25 further comprising the step of threading a cable from the weather compensation active component for connection to a boiler control unit through the balanced flue, and preferably through an air intake of the balanced flue, wherein this step takes place before the step of slotting the balanced flue through the wall.

27. The method of claim any of claims 25 or 26 further comprising the step of attaching the weather compensation active component to a portion of the balanced flue proximal to an air inlet of the balanced flue and outside a path of flue exhaust gas.

28. The method of any of claims 25 to 27 wherein the slotting of the balanced flue is done from the inside of a building.

29. The method of any of claims 25 to 28 wherein the weather compensation active component is detachably clipped to the balanced flue.