EP2926012A1

EP2926012A1 - Multiple speed fan and associated installation method

Info

Publication number: EP2926012A1
Application number: EP13799660.9A
Authority: EP
Inventors: Paul Sweeney; Nigel Simpson; Christopher KENTCH
Original assignee: Greenwood Air Management Ltd
Current assignee: Zehnder Group UK Ltd
Priority date: 2012-11-30
Filing date: 2013-11-29
Publication date: 2015-10-07
Also published as: GB2508422B; GB2508422A; WO2014083357A1

Abstract

There is provided a fan having a plurality of preset speed settings and a means to select one of the preset speed settings, wherein each of the preset speed settings is pre-calibrated for a particular installation scenario. There is also provided a method of installing a fan comprising the steps of: installing the fan in a selected installation location; performing a selected installation type; and selecting one of a number of preset speeds on the fan which matches said installation location and said installation type. Providing a number of preset speeds facilitates easy installation and reduces the risks of over-ventilation or under-ventilation due to errors in, or absence of, proper set up. The correct installation improves efficiency.

Description

MULTIPLE SPEED FAN AND ASSOCIATED INSTALLATION METHOD

The invention relates to fans, in particular to domestic ventilation fans such as extractor fans for use in a bathroom, kitchen or WC.

Extractor fans can be used in different settings within a building. The requirements of the fan may vary according to the setting in which it is to be used. For example it is generally desirable to extract air at a faster rate from a humid bathroom than from a less humid WC. Similarly, a higher ventilation rate is preferred from a kitchen during cooking.

The way a fan is installed also alters the resistance that the fan experiences when trying to move air from inside a room to outside. For example a fan which expels air through a significant length of ducting will generally experience higher resistance than one which is simply mounted in an external wall and which vents directly to the outside without ducting. The presence or absence of back flow shutters also affects resistance. The use of a window kit to mount an extractor fan in a window also adds resistance due to the need for a rear grille and backdraught shutter placed quite close to the rear end of the fan.

Therefore to achieve a given air flow rate may require different fan speeds in different circumstances. ideally, each fan would be calibrated on site after installation so that the motor speed would be set optimally for the particular installation location and the particular installation type. A flow meter would be used to measure the flow rate and the fan speed adjusted until the desired flow rate is achieved. However in practice installers often do not have the required calibration equipment such as a flow meter. Additionally many installers are lazy and do not wish to spend the time performing a proper calibration. if a fan has variable speed, an installer will often simply set it to maximum speed so as to ensure that it achieves the necessary ventilation for the circumstances.

However this results in unnecessary energy expenditure and noisier operation which could be avoided by proper calibration. In particular, when heating or cooling systems are used to raise or lower the temperature of air within the building, unnecessary extraction of that air represents an energy inefficiency as replacement air drawn in from outside must be heated or cooled to the required temperature again. This can be mitigated to a large extent with heat recovery systems, but in many properties, particularly older ones, such systems are not in use so venting warm air represents a direct energy loss.

According to the invention there is provided a fan having a plurality of preset speed settings and a means to select one of the preset speed settings, wherein each of the preset speed settings is pre-caiibrated for a particular installation scenario.

Each preset speed can be pre-calibrated for a given scenario and programmed into the fan in the factory. Therefore the setting can be guaranteed to have the correct speed setting by simply selecting the correct preset speed and without having to perform on site calibration. An installer simply has to choose which scenario applies from a list provided with the fan and select the appropriate setting. The fan will then be calibrated to extract sufficient air from the room for the given scenario, without extracting more air than is necessary. it will be appreciated that the calibration provided by this arrangement is not as accurate as on site calibration as it cannot take into account the exact installation situation, but the factors which are not taken into account represent only small speed variations which have negligible impact on the energy efficiency. The major influences on fan speed can be accommodated via the preset speed setting so that a suitable speed can be selected easily and with little effort by the installer.

Preferably the plurality of preset speed settings includes a plurality of speed settings for the same possible location, but calibrated for a plurality of possible resistances. For example the fan may include a plurality of bathroom settings. All of those bathroom settings are calibrated for the same expected location (a bathroom), but the settings differ according to the expected resistance. For example one bathroom speed setting may be calibrated for a fan installed in a window kit (i.e. with the fan mounted through a window pane), one bathroom speed setting may be calibrated for a fan installed directly in a wall, one bathroom speed setting may be calibrated for a fan installed with up to 1 ,5 metres of ducting between the inlet and the outlet and one bathroom speed setting may be calibrated for a fan installed with up to 3 metres of ducting between the inlet and the outlet. The resistance depends on a number of factors including the size of fan, size of duct, speed of air flow, presence of grilles, shutters, louvers, etc. There is no set relationship of resistances to installation types. These must be calibrated according to the circumstances. For example, a through-wail installation may provide less air resistance than a window kit which in turn may provide less air resistance than a fan installed with 3m of ducting. However, an installation in up to 1.5 metres of ducting may provide more or less resistance than a through-wall installation because the effect of the backdraught shutters may dominate in some

circumstances. The backdraught shutters are usually necessary on the through- wall installation and increase the air resistance. The fan speed required to achieve the desired ventilation rate therefore differs according to the installation type. The preset speeds provide a simple and easy way to set up the fan appropriately for the chosen installation type without having to perform on-site calibration.

Preferably the plurality of preset speed settings includes speed settings for more than one possible installation location. For example the fan may include one or more settings for a bathroom and one or more settings for a WC. Different installation locations require different ventilation rates according to their intended uses. For example a lower ventilation rate is required to sufficiently vent odours from a WC than is required to sufficiently vent humid air from a bathroom.

Alternatively, the fan may include one or more kitchen settings and one or more utility room settings. A kitchen/utility fan may be larger than a bathroom/WC fan, e.g a 150 mm diameter fan compared to a 100 mm diameter fan.

The fan may include preset speed settings for a plurality of possible locations and, for at least one of those possible locations, the preset speed settings may include a plurality of settings for different installation types (such as through-wall, window kit, ducting as described above). Preferably a plurality of settings for different installation types is provided for each possible location for which the fan is intended to be used. !n one particularly preferred embodiment, the fan may have a plurality of settings for each of two locations (e.g. a plurality of bathroom settings and a plurality of WC settings, or a plurality of kitchen settings and a plurality of utility room settings). The fan may provide three settings for each location (e.g. a window-kit setting, a through-wall setting and a ducted setting for each location setting). With two location settings and three installation types per location, six preset speeds would be provided, each precalibrated for the appropriate installation scenario (a scenario comprising a location and an installation type). However, it is preferred that settings are provided for two installation locations with one installation location being provided with more installation-types than the other installation location. This is because there will typically be one location which requires more variation in installation type. For example a WC typically only requires a low flow rate and the efficiency gains from multiple speed settings are minimal, whereas a bathroom installation will gain more from being accurately calibrated to the type of installation, so providing, e.g. four installation types is beneficial. In some preferred

embodiments the fan provides two preset speeds for one installation location and four preset speeds for a second installation location.

Preferably the controls for adjusting the fan have a simple and intuitive design. As mentioned above, installers are often under time-pressure and are disinclined to go through the proper procedure for installing and calibrating a fan to the correct settings. Therefore a complicated selection procedure will likely lead to a lack of attention to the setup and errors being made in setup. This will lead to poor performance either through under-ventilation if an inappropriately low setting is selected or through over-ventilation (and consequent heat wastage) if an inappropriately high setting is selected.

Therefore in preferred embodiments the controls to select a particular preset speed setting consist of an up button and a down button. Pressing the up or down button selects a different preset speed setting. In this way, continued pressing of one button will step through the preset speed settings in a progressive fashion. Pushing the other button will reverse the process.

The preset speed settings may be arranged in any order. For example settings for one location could be grouped so that various installation types for that location are adjacent to each other. Alternatively settings for a particular installation type could be grouped together so that settings for different locations are adjacent to each other. However it is preferred that the preset speed settings are arranged in speed order so that continued pressing of the up button will progressively increase the fan speed while continued pressing of the down button will progressively decrease the fan speed. With this arrangement, selecting the appropriate preset is still a simple matter, but in rare circumstances when an adjustment needs to be made (e.g. if the factory calibrated settings are not appropriate for some reason), it is still intuitive to select an alternative setting which is either higher speed or lower speed than the current setting.

Preferably a simple indicator is provided to indicate which setting is currently selected. The indicator may be a set of LEDs forming a pattern which can be matched to a list of the preset settings and the scenarios for which they are calibrated. Such a simple indicator minimises the space required for the display and thus allows the controls and indicator to be mounted in a space-efficient manner on the product.

The fan can be designed for intermittent operation or it can be designed for continuous running. However, the fan is preferably an intermittent fan as the invention has greatest applicability to intermittent fans. One reason for this is that continuous fans are more often installed in new build properties at the time of building when there is more likelihood of on site calibration being available, intermittent fans are more often used for retro-fitting in older, existing properties and are therefore installed by individuals or smaller contractors.

The invention also provides a method of installing a fan comprising the steps of: installing the fan in a selected installation location; performing a selected installation type; and selecting one of a number of preset speeds on the fan which matches said installation location and said installation type.

Preferred embodiments of the invention will now be described, by way of example only, and with reference to the drawings in which:

Figure 1 shows a fan unit according to an embodiment of the invention; Figure 2 shows the fan unit of Figure 1 with a cover removed; and

Figure 3 shows tables of fan modes and speeds.

Figure 1 shows a fan unit 100. Fan unit 100 is an intermittent fan, i.e. one designed to run for shorter periods of limited duration, but it will be appreciated that other embodiments may be continuous running fans.

The fan unit 100 has a main body 110 which houses a motor and impeller (not shown as well as electronics for controlling the motor and impeller. A mounting plate 120 is provided for mounting the fan unit 100 to a wall. Alternatively a window mounting kit (not shown) may be provided for mounting the fan unit 100 in a window. A decorative front plate 130 is provided substantially parallel to the mounting plate 120, but displaced therefrom so as to allow air to flow into the fan between the mounting plate 120 and the front plate 130. The front plate 130 provides a more aesthetic appearance to the user by hiding the impeller, the grille and the controls from view.

The fan unit 100 shown in Figure 1 is design for installation in a wall or window kit, but an equivalent version without the mounting plate 120 or front plate 130 can be used for mounting inline in ducting, e.g. in a ceiling void.

A pull cord 140 is provided which can be used for activating or inactivating the fan. Alternatively pull cord 140 may be omitted or disengaged and the fan can be activated/inactivated by a separate switch, e.g. a light switch.

Figure 2 is a front view of the fan unit 100 shown in Figure 1 , but with the decorative front plate 130 removed to show the controls 180, 170 and indicators 180. The impeller 105 can also be seen in this view. The fan is controlled by two buttons; an up button 180 and a down button 170. These buttons are used to select between different preset speed settings as described in more detail below.

An indicator 180 is provided which indicates which of the preset speed settings is currently selected. The indicator 180 comprises three LEDs 181 , 182 and 183 - - which are illuminated in a different unique pattern for each of the preset speed settings, it will be appreciated that the three LEDs 181 , 182, 183 can represent up to 8 different speed settings. If more than 8 speed settings are required, more LEDs can be used or an alternative display mechanism can be provided, such as one or more seven segment displays for displaying numerals. The use of simple LED patterns provides the benefit of simplicity and compactness. As shown in Figure 2, the control buttons 160, 170 and the indicator 180 are all contained within the spigot 150 at the centre of the fan unit 100 which houses the motor and the control electronics (PCBs). The spigot 150 is of restricted size so as to provide adequate air flow past it towards the impeller and therefore compactness is an important quality.

The spigot 150 also projects forward from the front plane of the mounting plate 120 and serves as a mount for the decorative front plate 130, thus again providing compactness of function. The front plate 130 must be removed in order to access the controls 160, 170 and so it is mounted in a bayonet fashion in bayonet mounts 190.

Figure 3 shows tables of example fan speeds for two embodiments of the invention. Table A is for a 100 mm fan designed for installation in either a WC or bathroom and in either a through-wall configuration, a window-kit configuration or a ducted configuration (with up to 3m of ducting). Table B is for a 150 mm fan designed for installation in either a utility room or kitchen and in either a through-wall

configuration, a window-kit configuration or a ducted configuration (with up to 3m of ducting). It will be appreciated that these speeds are provided as examples and are not intended to be limiting on the invention.

As shown by the information panel 185, each preset speed setting has its own unique LED pattern to be displayed by LEDs 181 , 182, 183. The preset speeds are arranged in an order so that pushing the up button 160 selects the next preset speed in the list (e.g. moves from preset 1 to preset 2 or from preset 2 to preset 3, etc.) and pushing the down button 170 selects the previous preset speed in the list. As can be seen from Fig. 3, the preset speeds are arranged in speed order so that pushing the up button 160 will always increase the fan speed (until the fastest setting is reached) and pushing the down button 170 will always decrease the fan speed (until the slowest setting is reached). This makes manual adjustment of the fan speed easier in unusual settings where the preset speed settings may not apply. The patterns provided for the indicator LEDs 181 , 182, 183 are also chosen so as to provide an intuitive indication of speed. Fewer LEDs are illuminated for lower speeds and a greater number of LEDs is illuminated for higher speeds. A single LED is used for preset speeds 1 , 2 and 3, a pair of LEDs is used for preset speeds 4 and 5 and all three LEDs are used for preset speed 6. To further distinguish these settings, higher placed LEDs are used to indicate faster speed settings. For example preset speed settings 4 and 5 both use two LEDs, but the faster speed setting (speed 5) is indicated with the two uppermost LEDs while the slower speed setting (speed 4) is indicated with the two lowermost LEDs. Each preset speed setting corresponds to a speed which has been calibrated in the factory for a particular installation scenario. An installation scenario in this embodiment is defined by an installation location and an installation type. It will be appreciated that in other embodiments further factors may be taken into account in defining an installation scenario. However in this embodiment just two factors are used (location and type).

As shown in Figure 3, two installation locations are covered by the settings; WC and bathroom. A fan installed in a bathroom is intended to exhaust relatively large quantities of warm moist air generated during bathing or showering and therefore needs to be run at a higher speed in order to provide a higher air flow rate through the fan and to expel the moist air relatively quickly. By comparison, a fan installed in a WC is only required to operate at a lower speed (lower air flow rate) in order to exhaust bad odours from the room. Not so much air needs to be exhausted and therefore operation at a lower flow rate is more energy efficient, while achieving the desired result. The lowest bathroom speed (speed 2) is slower than the highest WC speed (speed 3), but as discussed above, the presets are arranged in speed order for intuitive adjustment.

Figure 3 further shows that the preset speed settings cover four installation types. Not all installation types are used with each of the installation locations, but a sub- set of the possible combinations is selected to produce a total of 6 preset speed settings. The four types of installation covered by the settings are 1) through-wall installation where the fan is installed directly through a wail, typically with minimal or no ducting, but with backdraft shutters, 2) installation in a window kit, 3) installation with up to 1.5 m of ducting and 4) installation with up to 3 m of ducting. Each of these installation types provides a different amount of air resistance which affects the amount of air exhaust by the fan at a given fan speed. Therefore a faster fan speed is required for a given air flow rate as air resistance increases. A window kit installation provides air resistance due to the requirement for a compact design which means the exhaust grille is located quite close to the impeller. This provides a bottle neck for the air flow and hence air resistance. Similarly, ducting provides air resistance through friction of air with the interior surface of the duct. The longer the duct, the more air resistance there will be. in both the 100 mm and 150 mm fans, four installation types are provided for one location (utility room and bathroom) while only two are provided for the second location (WC or kitchen). A WC installation does not benefit so much from the efficiencies of different installation types due to its lower speed. E.g. there is not so much benefit to providing a setting for less than 1.5 metres of duct in addition to providing a setting for up to 3 metres of duct. A kitchen installation is unlikely to be in a ducted configuration as kitchens are nearly always located with external walls which are suitable for a through-wall or window kit installation.

Claims

1. A fan having a plurality of preset speed settings and a means to select one of the preset speed settings, wherein each of the preset speed settings is pre- calibrated for a particular installation scenario.

2. A fan as claimed in claim 1 , wherein the plurality of preset speed settings includes a plurality of speed settings for the same possible location, but calibrated for a plurality of possible resistances.

3. A fan as claimed in claim 1 or 2, wherein the plurality of preset speed settings includes speed settings for more than one possible installation location.

4. A fan as claimed in any preceding claim, including preset speed settings for a plurality of possible locations and for at least one possible location, the preset speed settings including a plurality of settings for different installation types.

5. A fan as claimed in claim 4, wherein a plurality of preset speed settings for different installation types is provided for each possible location.

6. A fan as claimed in any preceding claim, comprising a plurality of preset speed settings for each of two locations.

7. A fan as claimed in claim 6, comprising two settings for a first location and four settings for a second location.

8. A fan as claimed in any preceding claim, wherein controls to select a particular preset speed setting consist of an up button and a down button. 9, A fan as claimed in claim 8, wherein the controls are arranged such that the preset speed settings are in speed order so that pressing the up button

progressively increases the fan speed and pressing the down button progressively decreases the fan speed. 10. A method of installing a fan comprising the steps of: installing the fan in a selected installation location;

performing a selected installation type; and

selecting one of a number of preset speeds on the fan which matches said installation location and said installation type.