Building ventilation method and apparatus

Abstract

 The invention relates to a method and apparatus for ventilating a building (100) that comprises one or more general use areas (1,2) and one or more soiled air generating areas (3). The invention comprises a single air handling unit (29) that delivers atmospheric air (21) to both said general use areas (1,2) and said soiled air generating areas (3). The unit (29) exhausts soiled air from said soiled air generating areas (3) solely to the atmosphere and also extracts ventilated air from said general use areas (1,2) and either exhausts this air to the atmosphere or recycles it back to both the general use areas (1,2) and the soiled air generating areas (3).

Description

[0001] The invention relates to a method and an apparatus for ventilating a building having one or more general use areas and one or more soiled air generating areas, in particular, but not exclusively, wherein the one or more soiled air generating areas comprises one or more toilet, powder room, cloakroom, shower room or bathroom.

[0002] Buildings such as swimming pool complexes and leisure centres are generally divided into communal or general areas and areas where soiled air is generated. For example, in general or communal areas participants undertake recreational pursuits such as swimming or other sports and change clothing to prepare for such pursuits. Areas where soiled air is generated typically include toilets or showers. It is generally undesirable to mix used air from toilets and showers with used air from general or communal areas. For example, used air from showering areas may have an undesirably high moisture content caused by the water vapour generated by hot showers and used air from toilets may contain odorous contaminants or pollutants.

[0003] Therefore, to keep used air from toilets and changing rooms separate from general areas, such buildings are usually ventilated by two or more air handling units. Air handling units for general areas comprise a casing which houses extract and supply fans, filters and air heaters, as well as control dampers which allow a predetermined part of the extract air to be exhausted to atmosphere or recirculated according to the need for fresh air. By contrast, air handling units for soiled air generating areas do not include control dampers allowing recirculation, but exhaust all soiled air to atmosphere.

[0004] For this reason, previous ventilation systems required more than one air handling unit. A first air handling unit would continually heat and deliver atmospheric air to soiled air generating areas and used air would then be exhausted to atmosphere. Separate air handling units were additionally required to continually heat and deliver atmospheric air, and either exhaust or recirculate this air, as necessary, from the general areas.

[0005] Thus, as a first aspect of the invention there is provided the use of a single air handling unit to ventilate a building having one or more general use areas and one or more soiled air generating areas.

[0006] As a second aspect of the invention there is provided a method of ventilating a building having one or more general use areas and one or more soiled air generating areas which comprises the steps of:

(a) delivering atmospheric air to both of said one or more general use areas and said one or more soiled air generating areas via a single air handling unit;

(b) exhausting ventilation air from said one or more soiled air generating areas which is solely delivered to the atmosphere; and

(c) extracting ventilation air from said one or more general use areas by said single air handling unit and either exhausting this to the atmosphere or recycling this extracted air to both of said one or more general use areas and said one or more soiled air generating areas.

[0007] One advantage of the method of the invention is in energy saving which is potentially substantial. Unlike previous ventilation systems which continually heat atmospheric air and exhaust used air from soiled air generating areas to atmosphere, the method of the invention employs a single air handling unit which allows air from general areas, which is relatively clean, to be recirculated and delivered to both the general and soiled air generating areas. The ventilation method of the invention therefore requires less atmospheric air to be heated to an ambient room temperature and is therefore more energy efficient.

[0008] The invention also has the added advantage of simplification of construction, because a single air handling unit is utilised, instead of two or more. Such an arrangement eliminates the need for extra controls, power supply cabling and ductwork which not only reduces the space needed to provide such a system but also the time taken to install the device and the cost of installation.

[0009] It will be appreciated that references to "building" relate to references to any building having both one or more general use areas and one or more soiled air generating areas. For example, said building may be a swimming pool complex, golf club, leisure centre, public house, restaurant, hotel, health and fitness centre, conference suite, office block or any other similar building.

[0010] It will also be appreciated that references to "soiled air generating area" relate to references to any area within a building likely to create soiled or contaminated air. For example, soiled or contaminated air may be generated in a toilet, powder room, cloakroom, shower room or bathroom. More generally, contaminated air includes not only the byproducts of human toiletry, but also any other low level contaminants associated with other activities such as cooking, cleaning and light industrial activities.

[0011] It will likewise be appreciated that references to "general use area" relate to any area within the building which is outside of the above mentioned soiled air generating areas. For example, said general use area may be a swimming pool area, changing room area, a fitness area, a recreation area, a seating area, a working area, a sleeping area, a conference hall, a meeting hall, a drinking or eating area or the like.

[0012] It will be appreciated that the larger the general use area and soiled air generating area, the greater the economic advantage of having a single air handling unit rather than two or more.

[0013] Preferably, the method is applied to a building which is a swimming pool complex comprising a general use area having a swimming pool and changing area, and a soiled air generating area having one or more toilets and shower rooms.

[0014] It will be appreciated that steps (a)-(c) in the method above will likely be repeated continually.

[0015] In one preferred embodiment, the atmospheric air used in steps (a) and (c) is heated and/or cooled prior to being delivered to the one or more general use areas and the one or more soiled air generating areas to satisfy the temperature of an area with different requirements. It will be appreciated that differing general use areas and soiled air generating areas may require heating and/or cooling to differing temperatures. When air is required to be heated, it is preferably heated by using a boiler hot water system to heat the atmospheric air in one or more heat exchangers in which the level of heating is controlled by a modulating valve with a drive motor controlling the flow of boiler hot water. When air is required to be cooled, it is preferably cooled using a cooling heat exchanger in which the ventilation air is cooled either by the expansion of a refrigerant gas or flow of chilled water.

[0016] In a further preferred embodiment, the atmospheric air used in steps (a) and (c) is filtered prior to being delivered to the one or more general use areas and the one or more soiled air generating areas.

[0017] It will be appreciated that exhaustion of ventilation air to atmosphere in steps (b) or (c) may be achieved either by separately exhausting ventilated air directly to atmosphere by the exhaust fan as in step (b) and/or indirectly by exhausting ventilated air from said one or more general use areas to the atmosphere by the exhaust fan as in step (c). Both the direct exhaustion to atmosphere in step (b) and the indirect exhaustion in step (c) are controlled by motorized dampers and adjustment of the speed of the exhaust fan to ensure that the sum of the exhausted air from both areas is exhausted to atmosphere.

[0018] This feature has the advantage of reducing the number of fresh and exhaust air grilles to be included in the external fabric of the building.

[0019] According to a second aspect of the invention there is provided an air handling unit arranged to ventilate a building having one or more general use areas and one or more soiled air generating areas which comprises:

(a) an exhaust fan chamber arranged to exhaust ventilated air from said one or more general use areas and said one or more soiled air generating areas to atmosphere;

(b) an extract chamber arranged to either recycle ventilated air from said one or more general use areas or extract to the exhaust fan chamber; and

(c) a supply chamber arranged to provide supply air to said one or more general use areas and one or more soiled air generating areas either as recycled air from the extract chamber or fresh air from the atmosphere.

[0020] In one preferred embodiment, the supply chamber additionally comprises an air processing chamber.

[0021] In a further preferred embodiment, the air processing chamber comprises heating means. Preferably, the heating means comprise a hot water heating system controlled by a valve and motor arranged to pass air through a heat exchanger containing hot water.

[0022] In a yet further preferred embodiment, the air processing chamber comprises cooling means. Preferably, the cooling means comprise a refrigeration cooling exchanger.

[0023] In a yet further preferred embodiment, the air processing chamber comprises filtering means.

[0024] Preferably, the exhaust fan chamber comprises an exhaust fan which may be powered by an electric motor, more preferably the exhaust fan electric motor is speed controllable. The presence of the fan enhances and controls the variable proportion of exhaustion of ventilated air to the atmosphere.

[0025] Preferably, the exhaust fan chamber additionally comprises one or more (e.g. two) control dampers, each of which may be powered by an electric motor, which are arranged to control the variable proportion of ventilated air exhausted from the one or more soiled air generating areas or recycled in the extract chamber from the one or more general areas.

[0026] Preferably, the supply chamber additionally comprises one or more control dampers (e.g. two), each of which may be powered by an electric motor, which are arranged to control the variable proportion of recycled air from the extract chamber or fresh air from the atmosphere.

[0027] In a further preferred embodiment, the air handling unit additionally comprises a supply chamber fan section which is arranged to enhance the delivery of supply air to the one or more general use areas and one or more soiled air generating areas. Preferably, the supply chamber fan section comprises a supply fan which is powered by an electric motor, more preferably the supply fan electric motor is speed controllable.

[0028] Preferably, the air handling unit additionally comprises one or more supply air ducts which are arranged to supply air from the supply chamber fan section to the one or more general use areas and the one or more soiled air generating areas.

[0029] Preferably, the one or more supply air ducts are linked to the one or more general use areas and the one or more soiled air generating areas by one or more supply air grilles.

[0030] Preferably, the supply air grilles are located on the upper part of the one or more general use areas and the one or more soiled air generating areas. More preferably, the supply air grilles are located on the ceiling of said one or more general use areas and the one or more soiled air generating areas.

[0031] Preferably, the air handling unit additionally comprises one or more exhaust air ducts which are arranged to exhaust air from the one or more soiled air generating areas to the exhaust fan chamber.

[0032] Preferably, the air handling unit additionally comprises one or more extract air ducts which are arranged to extract air from the one or more general use areas to the extract chamber.

[0033] Preferably, the one or more exhaust air ducts are linked to the one or more soiled air generating areas by one or more exhaust air grilles.

[0034] Preferably, the one or more extract air ducts are linked to the one or more general use areas by one or more extract air grilles.

[0035] Preferably, the one or more exhaust air grilles and one or more extract air grilles are located in the lower part of the one or more general use areas and the one or more soiled air generating areas. In combination with supply air grilles in the upper part of the one or more general use areas and the one or more soiled air generating areas, this arrangement has the advantage of providing more efficient air distribution.

[0036] The motorized dampers and speed control of the exhaust fan allow the ventilation system to control the proportion of recirculated and fresh air within the supply ventilation in order to optimize the level of fresh air to maintain appropriate levels of freshness and/or humidity, and minimize energy consumption by the system.

[0037] An important advantage of this control system is that it enables the amount of fresh air used by the system during periods of non-occupation to be reduced to a minimum for increased energy conservation.

[0038] The control of the proportions of fresh and recirculated air in response to the level of humidity sensed in the general areas allows the system to maintain an appropriate level of humidity in the general areas.

[0039] This level of humidity may be fixed or varied in accordance with changes in outside temperature to avoid condensation on glazing.

[0040] A preferred application of this control of fresh and recirculated air system allows the humidity to be controlled in a swimming pool hall as general area. When the level of evaporation in the pool hall starts to increase with higher levels of bathing, the level of fresh air is increased by increasing the speed of the exhaust fan; increasing the opening of the fresh air damper; increasing the opening of the exhaust damper and decreasing the opening of the recirculation damper in the appropriate proportions as provided by a direct digital controller. At the same time the level of soiled air extracted to atmosphere may be kept constant.

[0041] Thus, in a yet further embodiment, the air handling unit additionally comprises sensing means arranged to monitor any one or more of the following conditions: internal air temperature; external air temperature; carbon dioxide level; and air humidity. Preferably, the air handling unit additionally comprises controlling means to effect a representative output signal in response to the sensing means.

[0042] The embodiment wherein the air handling unit is arranged to monitor external air temperature has the advantage of allowing control over the degree of heating or cooling required for atmospheric air to be heated to ambient room temperature. For example, on cold days or during the winter months, the external air temperature will be significantly cooler than ambient room temperature and therefore a greater degree of heating will be required and the controlling means will enhance the degree of heating generated by the heating means. Furthermore, on hot days or during the summer months, the external air temperature may be warmer than ambient room temperature and therefore may require cooling and the controlling means will enhance the degree of cooling generated by the cooling means.

[0043] The embodiment wherein the air handling unit is arranged to monitor internal air temperature also has the advantage of allowing control over the degree of heating or cooling required for atmospheric air to be heated to ambient room temperature. For example, if a large amount of used air from the one or more general use areas is being recirculated then this will require less heating than atmospheric air and the controlling means will reduce the degree of heating generated by the heating means. Therefore, this embodiment has the advantage of providing energy savings.

[0044] The embodiment wherein the air handling unit is arranged to monitor air humidity has the advantage of allowing control over the degree of recirculation of used air from the one or more general use areas. For example, if a large amount of used air has been recirculated then the sensing means may detect a moisture content in excess of a level by which it should be recirculated. In this situation, the controlling means will adjust the airflow within the air handling unit to divert the used air from the first exhaust chamber to the second exhaust chamber rather than further recirculate the used air to the first inlet chamber.

[0045] Carbon dioxide levels in air within the one or more general use areas or one or more soiled air generating areas are generally proportional to the number of people present at any given time within said areas. Thus, the embodiment wherein the air handling unit is arranged to monitor the carbon dioxide level provides the advantage of allowing control over the level of atmospheric air supplied to any given area. Thus, the level supplied will be appropriate with respect to the number of people present within a given area which is likely to vary. This embodiment therefore provides the advantage of additional energy saving.

[0046] A preferred embodiment of the invention will now be described with reference to the accompanying drawing in which:

Figure 1 shows a schematic representation of the building ventilation apparatus according to one embodiment of the invention.

[0047] Referring to Figure 1, a building shown generally as 100, comprises two general use areas 1,2 and a soiled air generating area 3. The building 100 is shown as a swimming pool complex wherein the first general use area 1 is shown as a leisure or swimming area, the second general use area 2 is shown as a changing room and the soiled air generating area 3 is shown as a toilet and shower room area. It will be appreciated that although the building 100 is shown in Figure 1 as a swimming pool complex, the invention finds wider applicability in a range of alternative buildings having one or more general use areas and one or more soiled air generating areas.

[0048] The first general use area 1 of the building 100 additionally comprises an air temperature sensor input 30, air humidity sensor input 31 and a carbon dioxide sensor input 33 which are all linked to a control panel 27 on an air handling unit, shown generally as 29. The control panel 27 contains controls for all apparatus of the invention and is powered by supply 38. A further sensor, 32 which monitors the outside air temperature is also linked to the control panel 27.

[0049] The first general use area 1 has a number of supply air grilles 5,6,7 located on the ceiling of the first general use area 1 which are linked to an air handling unit 29, by a supply air duct 4. The first general use area 1 additionally has an extract air grille 12 which is also linked to the air handling unit 29 by an extract air duct 40c, 40d.

[0050] The second general use area 2 has a supply air grille 8 located on the ceiling of the second general use area 2 which is linked to the air handling unit 29, by a supply air duct 4. The second general use area 2 additionally has an extract air grille 11 which is also linked to the air handling unit 29 by an extract air duct 40b, 40d.

[0051] The soiled air generating area 3 has a supply air grille 9 located on the ceiling of the soiled air generating area 3 which is linked to the air handling unit 29, by a supply air duct 4. The soiled air generating area 3 additionally has an exhaust air grille 10 which is also linked to the air handling unit 29 by an exhaust air duct 40a.

[0052] The air handling unit 29 comprises an exhaust fan chamber 34, extract chamber 35, supply chamber 36 and a supply chamber fan section 37.

[0053] The exhaust fan chamber 34 comprises a damper 28, modulated by a control motor 41 which controls the flow of ventilated air through the exhaust air duct 40a from the soiled air generating area 3. The exhaust fan chamber 34 also comprises an additional damper 16, modulated by a control motor 17 which controls the flow of ventilated air from the extract chamber 35 to the exhaust fan chamber 34. The exhaust fan chamber 34 also comprises an exhaust fan 15 powered by an electric motor for exhausting air to the atmosphere.

[0054] The extract chamber 35 comprises an extract air inlet 14 which controls the flow of ventilated air through the extract air duct 40b,40c,40d from the general use areas 1,2.

[0055] The supply chamber 36 comprises a damper 13, modulated by a control motor 20 which controls the flow of fresh air 21 into the supply chamber 36 from the atmosphere. The supply chamber 36 further comprises an additional damper 18, modulated by a control motor 19 which controls the flow of extracted air from the extract chamber 35 to the supply chamber 36. The supply chamber 36 additionally comprises an air processing chamber which comprises filtering means 22 for filtering the supply air and heating means 23 to heat the supply air. The heating means 23 comprises a hot water control valve 24 modulated by a motor 25.

[0056] The supply chamber fan section 37 comprises a supply fan 26 powered by an electric motor for supplying air to the supply air duct 4.

[0057] In use, fresh air 21 is drawn into the air handling unit 29 via the supply chamber 36. The flow of fresh air 21 from the atmosphere into the supply chamber 36 is controlled by a damper 13, which in turn is modulated by a control motor 20. Depending upon the outside air temperature, as monitored by the outside air temperature sensor 32, the control panel 27 will control the degree of heating required for the fresh air to reach a desired temperature for ventilation within the building 100. As appropriate, the fresh air is then filtered by the filtering means 22 and heated by the heating means 23 and then passes into the supply chamber fan section 37 before supply air is then provided to the building 100 into general use areas 1,2 and soiled air generating area 3. The flow of the supply air is controlled as necessary by the presence of the supply fan 26 and enters the building 100 through a series of supply air grilles 5,6,7,8,9 which are linked to the supply chamber fan section 37 by a supply air duct 4.

[0058] Ventilated air (i.e supplied air which has been used) is extracted from the first and second general use areas 1,2 of the building 100 through extract air grilles 11,12. The ventilated air then passes through the extract air duct 40b,40c,40d and enters the extract chamber 35 through the extract air inlet 14 which governs the flow of ventilated air through the extract air duct 40b,40c,40d from the general use areas 1,2.

[0059] In response to signals from the control panel 27, dependent upon temperature, humidity and carbon dioxide levels within the supply air as detected by sensors 30, 31, 32, 33 the extract chamber 35 either recycles ventilated air to the supply chamber 36 or exhausts the ventilated air to the exhaust fan chamber 34. For example, ventilated air which has been recycled is likely to increase in carbon dioxide, temperature and humidity and therefore once these factors have reached a certain level then the control panel will indicate that recycling should be reduced and an increase in fresh air should occur to reduce the carbon dioxide, temperature and humidity levels. This control is provided by dampers 16,18, which control the flow of extracted air from the extract chamber 35 to either the supply air chamber 36 or the exhaust fan chamber 34, as appropriate.

[0060] By contrast, if the carbon dioxide, temperature and humidity levels are within the guideline levels then ventilated air may continue to be recycled to the supply air chamber 36 and air flow will continue as discussed above.

[0061] Ventilated air from the extract chamber 35 which is exhausted to the exhaust fan chamber 34 is then exhausted to the atmosphere by the exhaust fan 15.

[0062] Ventilated air is extracted from the soiled air generating area 3 of the building 100 through exhaust air grille 10. The ventilated air then passes through the exhaust air duct 40a and enters the exhaust fan chamber 34 which is controlled by the damper 28. Ventilated air from the soiled air generating area 3 is then exhausted to the atmosphere by the exhaust fan 15.

Claims

1. A method of ventilating a building having one or more general use areas and one or more soiled air generating areas which comprises the steps of:

(a) delivering atmospheric air to both of said one or more general use areas and said one or more soiled air generating areas via a single air handling unit;

(b) exhausting ventilation air from said one or more soiled air generating areas which is solely delivered to the atmosphere; and

(c) extracting ventilation air from said one or more general use areas by said single air handling unit and either exhausting this to the atmosphere or recycling this extracted air to both of said one or more general use areas and said one or more soiled air generating areas.

2. A method as defined in claim 1 wherein the atmospheric air used in steps (a) and (c) is heated by a boiler hot water system and/or cooled by a cooling heat exchanger and/or filtered prior to being delivered to the one or more general use areas and the one or more soiled air generating areas.

3. An air handling unit arranged to ventilate a building having one or more general use areas and one or more soiled air generating areas which comprises:

(a) an exhaust fan chamber arranged to exhaust ventilated air from said one or more general use areas and said one or more soiled air generating areas to atmosphere;

(b) an extract chamber arranged to either recycle ventilated air from said one or more general use areas or extract to the exhaust fan chamber; and

(c) a supply chamber arranged to provide supply air to said one or more general use areas and one or more soiled air generating areas either as recycled air from the extract chamber or fresh air from the atmosphere.

4. The method or air handling unit as defined in any preceding claims wherein said building is a swimming pool complex comprising a general use area having a swimming pool and changing area, and a soiled air generating area having one or more toilets and shower rooms.

5. An air handling unit as defined in claim 3 or claim 4 wherein the supply chamber additionally comprises an air processing chamber comprising heating means, cooling means and/or filtering means.

6. An air handling unit as defined in any of claims 3 to 5 wherein the exhaust fan chamber and supply chamber additionally comprise one or more control dampers.

7. An air handling unit as defined in any of claims 3 to 6 wherein the air handling unit additionally comprises a supply chamber fan section.

8. An air handling unit as defined in any of claims 3 to 7 wherein the air handling unit additionally comprises a plurality of air ducts which are arranged to:

(a) supply air from the supply chamber fan section to the one or more general use areas and the one or more soiled air generating areas; and/or

(b) extract air from the one or more general use areas to the extract chamber; and/or

(c) exhaust air from the one or more soiled air generating areas to the exhaust fan chamber.

9. An air handling unit as defined in claim 8 wherein said one or more air ducts are linked to the one or more general use areas and the one or more soiled air generating areas by one or more air grilles.

10. An air handling unit as defined in claim 9 wherein the one or more air grilles are located in the lower part of the one or more general use areas and the one or more soiled air generating areas.

11. An air handling unit as defined in any of claims 3 to 10 wherein said air handling unit additionally comprises sensing means arranged to monitor any one or more of the following conditions: internal air temperature; external air temperature; carbon dioxide level; and air humidity.

12. An air handling unit as defined in claim 11 wherein said air handling unit additionally comprises controlling means to effect a representative output signal in response to the sensing means.

Drawing