WO2022045900A1

WO2022045900A1 - A ventilation unit and a system for ventilating an indoor space

Info

Publication number: WO2022045900A1
Application number: PCT/NZ2021/050148
Authority: WO
Inventors: Hasith Kanchana PUWAKDANDAWA
Original assignee: Itronics Limited
Priority date: 2020-08-31
Filing date: 2021-08-25
Publication date: 2022-03-03
Also published as: AU2021333082A1; NZ779410A; AU2021333082B2; US20240093902A1; AU2021333082A9

Abstract

A ventilation unit for providing forced ventilation of ambient air into an indoor space of a building is provided. The ventilation unit may be used to reduce the relative humidity of an indoor space and provide a more comfortable indoor space environment.

Description

A VENTILATION UNIT AND A SYSTEM FOR VENTILATING AN INDOOR SPACE

TECHNICAL FIELD

The present invention pertains in general to a ventilation unit. More particularly, the present invention relates to a ventilation unit for providing forced ventilation of ambient air into an indoor space of a building.

BACKGROUND

Indoor forced ventilation units may be used to improve the indoor climate in an indoor space by taking fresh air from an ambient area, e.g. the attic space or from the outside, and force this fresh ambient air into the indoor space. Forced ventilation provides circulation of air which may prevent mould from building up in the indoor space. The forced ventilation also allows for transfer of heat from the ambient area into the indoor space. Also, provided the air from the ambient area is clean or is filtered before reaching the indoor space, forced ventilation improves the air quality of the indoor space.

US Patent No. 6,450,414 discloses a heat transfer system for controlling the transfer of heat from a roof space into a living space of a building. The heat transfer unit includes a flexible duct and a ceiling vent for transferring warm air from within the roof space into a living space below. An electric fan located at the top end of the flexible duct is arranged to draw warm air from the roof space down through the duct into the living space. An electronic controller controls operation of the electric fan in response to temperature sensing signals from first and second temperature sensors respectively.

In order to achieve the desired benefits mentioned above the ventilation unit is only activated under certain ambient conditions. For example, in US Patent No. 6,450,414 the controller ensures that the electric fan is only activated when the air temperature within the roof space exceeds the air temperature within the living space by a predetermined temperature difference. The unit can also be employed in a cooling mode.

A general objective for most indoor forced ventilation units is to control the relative humidity of the indoor space such that is below a certain threshold, since a high relative humidity may lead to mould growth.

While forced circulation alone reduces the risk of mould growing in the indoor space to a certain extent, the overall risk of mould growing may be further reduced by maintaining a relative humidity of the indoor air below a certain threshold in the indoor space. Generally, in order to minimise the risk of mould to grow the relative humidity should remain below 70%, e.g. 60%, in the indoor space. When air is subject to cooling its relative humidity increases provided the total water vapour content, i.e. the absolute humidity level [g/m³], is held constant. Conversely, when air is subject to heating its relative humidity decreases provided the total water vapour content is maintained. The general objective of indoor forced ventilation units to control the relative humidity such as to be below a predetermined threshold dictates when the associated fan of the ventilation unit may be activated given the temperature of the ambient air temperature, humidity of the ambient air, temperature of the indoor space air, and/or humidity of the indoor space air.

When the ambient air is warmer than that of the indoor space, and/or when the ambient air has a lower moisture content than that of the indoor space, forced ventilation of ambient air into the air of the indoor space will result in a decreasing relative humidity in the indoor space.

The ambient air of attics and roof spaces normally has a lower moisture content during the cooler months of the year than that of the indoor spaces. Forced ventilation of the ambient air into the indoor space may therefore act to dry the indoor air under such conditions.

When the ambient air is cooler than that of the indoor space, and/or when the ambient air has a higher moisture content than that of the indoor space, forced ventilation of ambient air into the air of the indoor space will result in an increasing relative humidity in the indoor space. If the fan of the ventilation unit, providing the forced ventilation, is operating under these conditions there is a risk of the relative humidity of the indoor space to increase beyond acceptable levels. In order to avoid such a risk some commonly known ventilation units are designed to be inactivated, i.e. with their associated fan turned OFF, under such conditions, which may lead to prolonged periods of time when the associated fan is inactive and thus being unable to providing any forced ventilation.

An improved ventilation unit for forced ventilation of an indoor space would be advantageous.

SUMMARY

An object of the present invention is to provide a ventilation unit that improves the indoor climate of an indoor space of a building by providing forced ventilation of ambient air into the indoor space.

The disclosed ventilation unit allows for an extended active operation time period given the current ambient air or indoor space air conditions, while allowing for controlling the relative humidity or temperature of the indoor space air to meet a target level.

According to an aspect a ventilation unit for providing forced ventilation of ambient air into an indoor space bounded by a structure, e.g. an inner wall, outer wall, or inner ceiling, when installed in a flow passage provided through said structure is provided. The ventilation unit comprises: an inlet, an outlet providing access to the indoor space, in use, a fan arranged to draw ambient air into the ventilation unit via the inlet and expel air through the outlet. The ventilation unit further comprises a controller arranged to: access information associated with a target air condition (TAC) parameter of the indoor space air, and determine a TAC level of the associated TAC parameter. Further, the controller is arranged to access information from at least one first sensor arranged to sense a first air condition (AC1) parameter associated with the ambient air, in use, and determine an AC1 level of the associated AC1 parameter. Moreover, the controller is arranged to access information from at least one second sensor arranged to sense a second air condition (AC2) parameter associated with air in the indoor space, in use, and determine an AC2 level of the associated AC2 parameter. Furthermore, the controller is arranged to activate the fan when: (a) the TAC level equals the AC2 level while the AC1 level differs from the TAC level; or (b) the TAC level differs from the AC2 level to an extent while the TAC level differs from the AC1 level to an even greater extent, or (c) the TAC level differs from the AC2 level while the AC1 level is equal to the AC2 level.

Further, the controller is arranged to send a control signal to an external air treatment unit fluidly connected to the indoor space for controlling an operation mode of said external air treatment unit to bring the AC2 level closer to the TAC level based on the activation of the fan.

According to a second aspect a system for providing forced ventilation of ambient air into an indoor space bounded by a structure, e.g. an inner wall, outer wall, or inner ceiling, when installed in a flow passage provided through said structure is provided. The system comprises the ventilation unit of the appended claims and an external air treatment unit fluidly connected to the indoor space, in use.

According to a third aspect, a method of controlling the operation of a ventilation unit providing forced ventilation of ambient air into an indoor space bounded by a structure, e.g. an inner wall, outer wall, or inner ceiling, when the ventilation unit is installed in a flow passage provided through said structure is provided. The ventilation unit comprising an inlet, an outlet providing access to the indoor space, in use, and a fan arranged to draw ambient air into the ventilation unit via the inlet and expel said air through the outlet. The method comprises accessing, by the controller, information associated with a target air condition (TAC) parameter of air in the indoor space, and determining a level (TAC level) of the TAC parameter. Further, the method comprises accessing, by the controller, information from at least one first sensor arranged to sense a first air condition parameter (AC1) associated with the ambient air, in use, and determining a level (AC1 level) of the AC1 parameter. Moreover, the method comprises accessing, by the controller, information from at least one second sensor arranged to sense a second air condition parameter (AC2) associated with air in the indoor space, in use, and determining a level (AC2 level) of the AC2 parameter. Furthermore, the method comprises activating the fan when: (a) the TAC level equals the AC2 level while the AC1 level differs from the TAC level; or (b) the TAC level differs from the AC2 level to an extent while the TAC level differs from the AC1 level to an even greater extent while the AC1 level and AC2 level are either both higher or both lower than the TAC level, or (c) the TAC level differs from the AC2 level while the AC1 level is equal to the AC2 level. Further, the method comprises sending a control signal to an external air treatment unit fluidly connected to the indoor space for controlling the operation mode of said external air treatment unit to bring the AC2 level closer to the TAC level based on the activation of the fan. According to a fourth aspect, a method of controlling the operation of a ventilation unit providing forced ventilation of ambient air into an indoor space bounded by a structure, e.g. an inner wall, outer wall, or inner ceiling, when the ventilation unit is installed in a flow passage provided through said structure is provided. The ventilation unit comprises an inlet, an outlet providing access to the indoor space, in use, and a fan arranged to draw ambient air into the ventilation unit via the inlet and expel said air through the outlet. The method comprises receiving user/app settings information associated with the operation settings of the ventilation unit. Further, the method comprises accessing, by the controller, information associated with a target air condition (TAC) parameter of air in the indoor space, and determining a level (TAC level) of the TAC parameter, information from at least one first sensor arranged to sense a first air condition parameter (AC1) associated with the ambient air, in use, and determining a level (AC1 level) of the AC1 parameter, and information from at least one second sensor arranged to sense a second air condition parameter (AC2) associated with air in the indoor space, in use, and determining a level (AC2 level) of the AC2 parameter. Moreover, the method comprises determining whether the accessed information is indicative of at least one of adverse air conditions or neutral or nonworsening air conditions. Furthermore, the method comprises activating the fan: (a) under adverse air conditions when the TAC level equals the AC2 level while the AC1 level differs from the TAC level; or (b) under adverse air conditions when the TAC level differs from the AC2 level to an extent while the TAC level differs from the AC1 level to an even greater extent while the AC1 level and AC2 level are either both higher or both lower than the TAC level, or (c) under neutral or nonworsening conditions when the TAC level differs from the AC2 level while the AC1 level is equal to the AC2 level. Further, the method comprises sending a control signal to an external air treatment unit fluidly connected to the indoor space for controlling the operation mode of said external air treatment unit to bring the AC2 level closer to the TAC level based on the activation of the fan.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to explain the invention, a number of embodiments of the invention will be described below with reference to the drawings, in which:

Fig. 1 shows a ventilation unit in a forced ventilation configuration according to an embodiment;

Fig. 2 shows a ventilation unit in a forced ventilation configuration according to an embodiment when installed into an inner ceiling of a building;

Fig. 3 shows a flow chart of a method according to an embodiment;

Fig. 4 shows a ventilation unit in an extraction fan configuration according to an embodiment;

Fig. 5 shows a ventilation unit in a forced ventilation configuration according to an embodiment when installed into an inner ceiling of a building; and Fig. 6 shows a further flow chart of a method according to an embodiment.

DETAILED DESCRIPTION

An idea of the present invention is to provide a ventilation unit for providing forced ventilation of ambient air into an indoor space of a building, wherein the ventilation unit is capable of sending an operation control signal to an external air treatment unit, thereby controlling an operation mode of the external air treatment unit. By being able to control an operation mode of the external air treatment unit, the ventilation unit may provide forced ventilation even under air conditions where the characteristics the ambient air alone would move an air condition parameter of the indoor space further away from a set target air condition parameter of the indoor space by operating the fan. This allows for providing forced ventilation even when the relationship between the characteristics of the ambient air and that of the air of the indoor space are not ideal, as will be further elucidated below.

In an embodiment according to Fig. 1 a ventilation unit 10 for providing forced ventilation of ambient air into an indoor space of a building is provided. The ventilation unit 10 is adapted to be installed at least partly in a flow passage 200 provided in a structure 201 bounding the indoor space 202 as shown in Fig. 2. The flow passage 200 allows fluid access between an ambient area 203 located at a side of the structure 201 opposing that of the indoor space 202, and the indoor space 202.

The structure may for example be an inner wall, outer/exterior wall, and/or inner ceiling or a floor having a cavity beneath or the like. The ambient area may be an attic space, roof space below the outer roof of the building, a further indoor space, the exterior side of the building, a cavity between an inner ceiling and a floor above it, or any cavity or space bounded by the structure 201 where air is present. Hence, the ventilation unit may be provided in a flow passage between two adjacent rooms of a building to provide forced ventilation between the rooms.

The ventilation unit 10 comprises an inlet 11 for receiving ambient air from the ambient area 203. The ventilation unit 10 further comprises an outlet 12 providing access to the indoor space 202, in use. The inlet 11 and/or outlet 12 may be arranged in a housing or insert of the ventilation unit 10.

The inlet 11 is in fluid communication with the outlet 12 to allow ambient air drawn into the inlet 11 to be expelled through the outlet 12.

The ventilation unit further comprises a fan 13 arranged to draw ambient air into the ventilation unit 10 via the inlet 11 and expel air through the outlet.

Further, the ventilation unit 10 comprises a controller 14. The controller 14 is arranged to control the operation of the fan, when certain air conditions are met.

Further the controller 14 is arranged to access information associated with a target air condition parameter (TAC) of the indoor space air. Based on the accessed information the controller is arranged to determine a level of the associated TAC based on the accessed information.

The controller 14 if further arranged to access information from at least one first sensor 17a arranged to sense a first air condition parameter (AC1) associated with the ambient air, in use. The controller 14 is arranged to determine a level of the associated AC1 based on the accessed information.

The controller 14 is further arranged to access information from at least one second sensor 18a arranged to sense a second air condition parameter (AC2) associated with air in the indoor space 202, in use, and determine a level of the associated AC2 based on the accessed information.

In an embodiment, the controller 14 is arranged to activate the fan 13 whenever the AC1 level of the ambient air will bring the AC2 level of the indoor space air closer to the TAC level of the indoor space air, when the ambient air is introduced into the indoor space air.

The controller 14 may also be arranged to activate the fan 13 whenever the AC1 level of the ambient air is equal to the AC2 level of the indoor space air so that the introduction of the ambient air into the indoor air would not move the AC2 level of the indoor space air away from the TAC level.

In an embodiment, the controller 14 is arranged to send a control signal to an external air treatment/ conditioning unit 300 fluidly connected to the indoor space for controlling an operation mode of said external air treatment unit 300 to bring the AC2 of the indoor space air level closer to the TAC level.

In some embodiments, the controller 14 is arranged to send a control signal to an external air treatment/conditioning unit 300 fluidly connected to the indoor space for controlling an operation mode of said external air treatment unit 300 to maintain the AC2 level constant. By controlling the external air treatment unit 300 to maintain the AC2 constant while the fan 13 is activated to force air from the ambient area under adverse air conditions into the indoor space, it is possible to prevent worsening the indoor space air. Operating the external air treatment unit 300 to maintain the AC2 level under adverse air conditions may require less energy than operating the external air treatment unit to bring the AC2 level towards the TAC level under the same conditions.

Since the controller 14 is capable of controlling an operation mode of an external air treatment/conditioning unit 300 it is possible to operate the fan of the ventilation unit even in adverse conditions, i.e. where the AC1 level of the ambient air will act to bring the AC2 level of the indoor space air further away from the TAC level when the ambient air is introduced into the indoor space, thereby allowing for the benefits of forced ventilation. The adverse tendency of the AC2 level moving further away from the TAC level by operation of the fan under such adverse conditions is overcome by the simultaneous operation of the external air treatment/conditioning unit, which is controlled by the controller to at least prevent the AC2 level of the indoor air to move further away from the TAC level, and/or moving the AC2 level of the indoor space air to the TAC level.

Air condition parameter and the associated levels

The target air condition parameter (TAC) may relate to any desired air condition parameter, e.g. air temperature, air humidity, relative air humidity, absolute air humidity, and/or air particle content. The level of the TAC parameter may relate to a quantitative measure of the TAC parameter provided in any given unit of measure.

Similarly, to the TAC parameter the AC1 parameter may relate to any desired air condition parameter, e.g. air temperature, air humidity, relative air humidity, absolute air humidity, and/or air particle content. The level of the AC1 parameter may relate to a quantitative measure of the AC1 parameter provided in any given unit of measure.

Similarly, to the TAC and AC1 parameters, the AC2 parameter may relate to any desired air condition parameter, e.g. air temperature, air humidity, relative air humidity, absolute air humidity, and/or air particle content. The level of the AC2 parameter may relate to a quantitative measure of the AC2 parameter provided in any given unit of measure.

In an embodiment, the controller is arranged to utilize the same unit of measure for each of the TAC level, AC1 level, and/or AC2 level.

Air condition parameter information

According to an embodiment, information, e.g. data, of the associated air condition parameter(s), e.g. AC1, and AC2, that is accessed by the controller 14 may be provided by means of one or more sensor(s) 17a, 18a.

In an embodiment, the ventilation unit comprises least one first sensor 17a (hereinafter referred to as AC1 sensor or an upstream sensor) for sensing information/data associated with the ambient air condition parameter AC1.

Alternatively, or additionally, the ventilation unit 10 may comprise at least one second sensor 18a (hereinafter referred to as AC2 sensor or a downstream sensor) for sensing information/data associated with the indoor space air condition parameter AC2.

According to one embodiment, at least one of the AC1 sensors, and/or AC2 sensors may be wired or wirelessly connected to the controller.

Hence, while some sensors may be arranged integral with the ventilation unit the controller 14 may be capable of accessing information/data from any number of wireless sensors located at a remote location.

Types of sensors For example, a wireless temperature and/or humidity sensor could be used to sense associated AC2 parameter(s). When the indoor space is bedroom, such an AC2 sensor could optionally be sitting on a bedside table, as opposed to being built into the ventilation unit itself.

Similarly, a wireless temperature and/or humidity sensor could be used to sense the associated AC1 parameter(s). One or more of such AC1 sensors could be arranged in the ambient area, e.g. attic or roof space to be wirelessly accessed by the controller 14. As an example, a one centralized wireless AC1 sensor could be used to sense the AC1 parameter. However, alternatively more than one AC1 sensor could be arranged throughout the ambient area to be accessed by the controller 14.

In an embodiment, at least one AC1 sensor is arranged in the vicinity of the inlet 1 of the ventilation unit. For example, the at least one AC1 sensor may be physically arranged in the ventilation unit, e.g. in a housing portion thereof. Optionally, the at least one AC1 sensor may be arranged discretely away from the ventilation unit so as to minimize the risk of any interference and possible incorrect readings of the associated AC1 parameter

In some embodiments, the controller is arranged to access information about the same AC1 or AC2 parameter, e.g. temperature, relative humidity, from more than one sensor, and determine a respective AC1 and/or AC2 level based on the plural sensors. For example, the controller 14 may be arranged to process the accessed information by averaging the information of the plural sensors to determine associated AC1 levels, and/or AC2 levels.

In an embodiment, at least one of the AC1 sensors is a temperature sensor wherein the associated AC1 parameter relates to ambient air temperature.

Additionally, or alternatively, at least one of the AC1 sensors may be a humidity sensor, relative humidity sensor, or absolute humidity sensor, wherein the associated AC1 parameter relates to ambient air humidity.

In some embodiments, at least one of the AC1 sensors is a combined temperature and humidity sensor.

According to an embodiment, at least one of the AC1 sensors is an air particle sensor, wherein the associated AC1 parameter relates to ambient air particle content.

In an embodiment, the one of the at least one AC2 sensor is a temperature sensor, wherein the associated AC2 parameter relates to air temperature.

Additionally, or alternatively, at least one of the AC2 sensors may be a humidity sensor, relative humidity sensor, or absolute humidity sensor, wherein the associated AC2 parameter relates to the humidity of the indoor space air.

In some embodiments, at least one of the AC2 sensors is a combined temperature and humidity sensor.

According to an embodiment, at least one of the AC2 sensors is an air particle sensor, wherein the associated AC2 parameter relates to particle content of the indoor space air. In some embodiments, the controller 14 is arranged to deactivate the fan when a level, e.g. AC1 level or AC2 level, of the air particle content exceeds a safety threshold.

One or more of the at least one AC2 sensor may be arranged in the vicinity of the outlet. For example, at least one AC2 sensor may be physically arranged in the ventilation unit, e.g. in a housing portion thereof at the outlet end of the ventilation unit. Such an AC2 sensor could be arranged at a location of the ventilation unit shielded from the flow path of the ambient air to minimise potential risk of any incorrect reading. Optionally, the at least one AC2 sensor may be arranged discretely away from the ventilation unit, e.g. at any location deemed suitable in the indoor space.

It should be appreciated that one or more of the at least one first AC1 sensor may be an external sensor or a sensor integral with the ventilation unit 10. Similarly, one or more of the at least one AC2 sensor may be an external sensor or a sensor integral with the ventilation unit 10.

In some embodiments, the ventilation unit further comprises a motion detector, e.g. an occupancy sensor, operatively coupled to the controller. The controller may be arranged to execute one or more specific tasks based on receiving a signal from the motion detector. The specific task(s) could e.g. be default task programmed into the controller, or tasks that are programmed into the controller via a user utilizing a second interface as will be further elucidated below. For example, based on receiving a signal from the motion detector relating to a detected presence of a moving object, e.g. a person, a specific task executed by the controller may be to lower the fan speed, by a certain increment or to a certain speed setting, to reducing the noise levels when a person is present in the room.

Alternatively, or additionally, based on a receiving a signal from the motion detector relating to no presence of a moving object, e.g. a person, or after a programmable time period has passed without receiving a signal from the motion detector relating to the presence of a moving object, the specific task executed by the controller may be to increase the fan speed to an original setting, by a certain increment or to a certain setting speed, to increase the forced ventilation when a person is not present or moving around in the room.

Alternatively, the motion detector may be used to supplement an existing home security systems by acting as a wired motion detector, when operatively coupled to such home security system.

Activation of the fan under adverse air conditions

As further elucidated above the controller 14 may be arranged to activate the fan 13 even under adverse air conditions for the benefit of providing forced ventilation of fresh air, with the result of moving the AC2 level away from the desired TAC level. Adverse conditions are present when the ambient air if introduced into the indoor space, would move the AC2 level of the indoor space air, further away from the desired TAC level of the indoor space air. In an embodiment, the controller 14 is arranged to activate the fan 13 when the TAC level equals the AC2 level while the AC1 level differs from the TAC level. This situation could be expressed as: TAC level = AC2 level, AC1 levelo TAC level.

When the fan is activated under such conditions, the AC1 level of the ambient air being introduced into the indoor space, will affect the AC2 level of the indoor space to move away from the TAC level of the indoor space.

As an example, with temperature as the given air condition parameter, the indoor TAC level is being set to 20°C. At a given point in time the AC2 level equals the TAC level of 20°C. Ambient air with an AC1 level of 18°C would if introduced into the indoor space act to cool the indoor space, thus lowering the AC2 level temperature, thus moving the AC2 level away from the TAC level. In such a situation the controller 14 is arranged to control the operation mode of the external air treatment unit to bring the AC2 level back to the desired TAC level, while operating the fan 13 in its activated state.

The controller may determine whether the air conditions are adverse from a humidity perspective by determining whether the relative humidity will be increased if the ambient air is introduced into the indoor space air. Such a determination may be based on commonly known moisture balance calculations. For example, the saturation water vapour pressure [Pa] for the respective area may be derived from a formula with the current area temperature as input. The water vapour pressure [Pa] in the respective area may be derived from a formula with the associated relative humidity as input. The absolute humidity [kg/m³] may then be derived from the ideal gas law formula with water vapour pressure, current temperature, and the gas constant for water as input. When the absolute humidity in each area has been calculated, it is possible to predict the mixed indoor space relative humidity, optionally factoring in the indoor volume and ambient area volume and/or or the volumetric flow rate of the fan at a certain speed setting. However, it should be appreciated that any known calculations may be used, including data associated with a known Moeller diagram, or data associated with a known psychrometric chart.

Alternatively, the controller may determine that adverse humidity conditions are present when the relative humidity in the ambient area is higher than that associated with the indoor space.

In an embodiment, the controller 14 is arranged to activate the fan 13 when the TAC level differs from the AC2 level to an extent while the TAC level differs from the AC1 level to an even greater extent and while the AC1 level and AC2 level are either both higher or both lower than the TAC level. In other words, in this situation the AC1 level and AC2 level found on the same side of the TAC level. This situation could be expressed as: TAC level >AC2 level > AC1 level or TAC level < AC2 level < AC1 level.

As an example, with temperature as the given air condition parameter, the indoor TAC level is being set to 20°C. The current AC2 level is 19°C, whereby the TAC level differs from the AC2 level by 1°C. If the AC1 level is 18°C the TAC level differs from the AC1 level by 2°C, which is greater than the 1°C difference between the TAC level and the AC2 level. Also, both the AC1 level and AC2 levels are lower than the TAC level. Hence, if the ambient AC1 level air would be introduced into the indoor space it would act to cool the indoor space, thus lowering the AC2 level temperature further, thus moving the AC2 level away from the TAC level. By controlling the operation mode of the external air treatment unit, the controller 14 is arranged to bring the AC2 level back to the desired TAC level, while operating the fan 13 in its activated state.

In an embodiment, the controller 14 is arranged to activate the fan 13 when the TAC level is lower than the AC2 level while the AC2 level is lower than the AC1 level.

In an embodiment, the controller is arranged to activate the fan 13 when the TAC level is higher than the AC2 level while the AC2 level is higher than the AC1 level.

In adverse air conditions, the external air treatment unit 300 and the fan 13 are actively operating in parallel. Accordingly, the controller is arranged to control the operation mode of the external air treatment unit 300 while the fan is activated. The fan 13 and external air treatment unit 300 may for example be controlled by the controller 14 to continue to run in parallel until a predetermined time period has lapsed or until the AC2 level has reached the TAC level.Activation of the fan 13 during neutral or non-worsening air conditions

In an embodiment, the controller 14 is arranged to activate the fan 13 during neutral or non-worsening air conditions. Such neutral or non-worsening air conditions may e.g. be when the TAC level differs from the AC2 level (TAC level <> AC2 level) while the AC1 level is egual to the AC2 level (AC1 level = AC2 level). Hence, while the operation of the fan 13 will not act to move the AC2 level further away from the TAC level, the controller is arranged to control the operation mode of the external air treatment unit to bring the AC2 level closer to the TAC level while the fan 13 is activated.

In an embodiment, the controller 14 is arranged to activate the fan 13 when the TAC level is lower than the AC2 level while the AC2 level is egual to the AC1 level. This could be expressed as: TAC level < AC2 level, AC2 level = AC1 level.

In an embodiment, the controller is arranged to activate the fan 13 when the TAC level is higher than the AC2 level while the AC2 level is egual to the AC1 level. This could be expressed as: TAC level > AC2 level, AC2 level = AC1 level.

Neutral or non-worsening air conditions may also exist when the AC1 level is egual to the TAC level (TAC level = AC1 level). In an embodiment, the controller 14 is arranged to activate the fan 13 under such conditions to provide the benefits of forced ventilation of fresh air. If the AC2 level differs from the TAC level (TAC level <> AC2 level) under these situations, the activation of the fan 13 will bring the AC2 level closer to the TAC level.

Further, according to some embodiments, if the difference between the AC2 level and the TAC level meets a pre-set threshold (e.g. expressed as |TAC level - AC2 level | > threshold) the controller is arranged to control the operation mode of the external air treatment unit to bring the AC2 level closer to the TAC level at a faster rate. The pre-set threshold may be set by a user using the second interface as further elucidated below.

Activation of the fan during favourable air conditions

Favourable air conditions exist when the when the AC1 level ambient air if introduced into the indoor space will move the AC2 level indoor space air towards the desired TAC level of the indoor space air. Expressed alternatively, favourable air conditions are present when the AC1 level is on the opposite side of the TAC level in view of the AC2 level, e.g.

AC1 level <TAC level <AC2 level, or

AC1 level >TAC level >AC2 level.

In some embodiments, the controller is arranged to activate the fan 13 based on a determination that favourable air conditions exist.

Modes of operation with no external heat treatment unit available

In some modes of operation, the controller is arranged to run through a loop where it checks sensors (AC1, AC2, motion sensors, smoke detectors), checks for contact closure inputs, checks for app commands, and then compares current AC1 levels and AC2 levels to thresholds (TAC levels) and makes a decision whether or not to activate the fan.

Max Auto Drying Mode

In an embodiment, the ventilation unit is arranged to operate in a MAX Auto Drying mode, selected by the user. In the MAX Auto Drying mode the fan is activated by the controller, at a given fan speed set by the user, when the difference between the AC1 (upstream) relative humidity level and the AC2 (downstream) relative humidity level is equal to or larger than a settable first humidity threshold. In other words, the fan is activated when the ambient area air is dryer than the indoor space air by a certain threshold. For example, the first humidity threshold may be set to 5% or any number above 0 and below 100. The first humidity threshold may be set by the user or set as part of the software the controller is running, and may be updated in firmware updates, etc.

As an example, if the Mode is set to Max Auto Drying Mode, and the AC1 (upstream) level is 70% and the AC2 level (downstream) is 75%, the controller is arranged to activate the fan, since the upstream air is at least 5% dryer than the indoor space air.

The controller will continue to keep the fan activated until the ambient area is no longer dryer than the indoor space by the set threshold.

Min Auto Drying Mode: In an embodiment, the ventilation unit is arranged to operate in a user selectable Min Auto Drying mode, selected by the user. In the Min Auto Drying mode the fan is activated by the controller, at a given fan speed set by the user, when the difference between the AC1 (upstream) humidity level and the AC2 (downstream) humidity level is equal to or larger than a second settable humidity threshold (wherein second humidity threshold being larger than the first humidity threshold), while the absolute value of the difference between the AC1 (upstream) temperature level and the AC2 (downstream) temperature level is equal or less than a first temperature threshold. In other words, in the Min Auto Drying Mode the fan will only be activated when the ambient area is substantially dryer than the indoor space area, and while the ambient area temperature is +/- a certain threshold from the current indoor space temperature.

In some embodiments, the second humidity threshold may be set to 15% or any number higher than the first humidity threshold and below 100%.

In an embodiment, the ventilation unit is arranged to operate in a user selectable Moderate Auto Drying mode. The Moderate Auto Drying mode the fan is activated by the controller, at a given fan speed set by the user, when the difference between the AC1 (upstream) humidity level and the AC2 (downstream) humidity level is equal to or larger than a third settable humidity threshold, while the absolute value of the difference between the AC1 (upstream) temperature level and the AC2 (downstream) temperature level is equal or less than a second temperature threshold. Here, the third humidity threshold is selected from a range between but not including the first humidity threshold and the second humidity threshold). The second temperature threshold can be selected from a range the range between but not including zero to the first temperature threshold.

The third humidity threshold and the second temperature threshold may be set by the user in the app by using a slider bar that can be moved between the Min Auto Drying Mode at one end of the slider and the Max Auto Drying Mode at the other end of the slider bar. Both the third humidity threshold and second temperature threshold may be set using a single slider with the respective level dependent on the relative or proportional distance between the end points of the slider associated with the Min Auto Drying Mode thresholds and the Max Auto Drying Mode thresholds, respectively.

For example, when the slider is set 1/4 of the way from Min Auto towards the Max Auto end point, the third humidity threshold may be calculated as the second humidity threshold (which is larger than the first humidity threshold) subtracted by 1/4 of the absolute value of the difference between the first humidity threshold and the second humidity threshold. Hence, in the example of the second threshold (Min Auto mode) of 15% and the first threshold (Max Auto mode) of 5%, the third threshold may be calculated by the controller as: 15%-(l/4)*abs(15-5) = 15%-2.5%=12.5%, Turning to the second temperature threshold although no threshold is given for the MAX Auto mode, as the fan is activated regardless of the temperature difference, for the purpose of calculating the second temperature threshold, the controller may assign a relatively high max threshold, e.g. 50°C to the MAX Auto Mode. This relatively high threshold is derived based on the assumption that the fan would be activated in the MAX Auto Drying mode if in addition to the first humidity threshold also the temperature difference between the ambient area and the indoor space is below the max threshold, and that the max threshold is set so that this always is the case at the location of installation of the ventilation unit.

The other end point of the slider bar, relating to the MIN Auto Drying mode, is associated with the first temperature threshold.

For example, when the slider is set 1/4 of the way from the Min Auto Drying end point towards the Max Auto Drying end point, the second temperature threshold may be calculated as the first temperature threshold (which is smaller than the max temperature threshold) added by 1/4 of the absolute value of the difference between the max temperature threshold and first temperature threshold. Hence, in the example of the first temperature (Min Auto mode) of 2°C and the max temperature (Max Auto mode) of 50°C, the second temperature threshold may be calculated by the controller as 2°C +(l/4)*abs(50°C -2°C) = 2°C+12°C =14°C,

It should be appreciated that each of the thresholds given above may be set to any level as long as their respective relationship, e.g. the second humidity threshold needing to be larger than the first humidity threshold, are complied with.

In some embodiments, the Auto Drying modes, including the Max Auto Drying mode, Min Auto Drying mode, and Moderate Auto Drying Mode, are only activated by the controller when the indoor space area, i.e. AC2 humidity level is equal to or above an activation threshold. In some embodiment, the activation threshold may be set to 60% or between 60% to 70%. This means that the fan will only be activated when the indoor area has an equal or higher relative humidity than activation threshold.

Example illustrating the MIN Auto Drying mode and MAX Auto Drying mode

Manual ON/OFF mode

In an embodiment, the ventilation unit may be operated in a Manual ON/OFF mode. In the manual ON/OFF mode the user is able to activate the fan to manual ON or manual OFF, irrespective of any AC1, AC2, or TAC levels.

Controller

The controller is may in its simplest form comprise a processor, e.g. a microprocessor, having computer processing capabilities and a memory. It should be appreciated that the controller may be any commonly available controller able to execute the functional steps disclosed herein, and/or software instructions associated with the operation of the ventilation unit and the external air treatment unit.

The controller may comprise or be operatively coupled to a wireless communication interface of the ventilation unit for wirelessly receiving data from and sending data to a connected wireless device, e.g. user device, smart phone, tablet, sensors, etc. The wireless communication interface may be arranged to communicate over any communication standard, e.g. WLAN/WIFI (including any IEEE 802.11 protocol), Bluetooth, or mobile broadband (GSM/2G/3G/4G/5G).

In some embodiments, the ventilation unit comprises a WIFI extender interface arranged to provide an extended WIFI network surrounding the location of the ventilation unit. The WIFI extender interface may be arranged to extend an existing wireless LAN network or wired LAN network in the building in which the ventilation unit is installed.

Alternatively, the WIFI extender interface may be arranged to create a local WIFI network around the ventilation unit in the event no local network is available, where the local WIFI network allows devices to connect thereto, e.g. for controlling the operation of the ventilation unit from a smart phone via the second interface. In some embodiments, the WIFI extender interface is designed to be added to the existing wireless LAN network, by receiving an existing WIFI signal from an existing wireless router and re-broadcasting it. The received signal may be broadcast on a different wireless channel so as to maintain the bandwidth. In this mode the WIFI extender interface operates as a WIFI range extender.

Additionally, or alternatively, the WIFI extender interface may be connected via wire to the gateway or WIFI router and create a second WIFI boosted network for devices to connect to. Signals received over the second WIFI boosted network from any connected devices are then communicated back to the gateway or router via the wire. In this mode the WIFI extender interface operates as a WIFI network extender. In addition to the benefits of providing a high speed WIFI network surrounding the location of the ventilation unit for any device, a further advantage of the WIFI extender interface is to enable the ventilation unit to be controlled by a local device, e.g. smart phone, connected to the same WIFI network, via the second interface of the ventilation unit without requiring any Internet connection. This allows for the ventilation unit to be controlled over the local WIFI extended network in areas, e.g. remote locations, where Internet access is limited or non-existing. Given, the WIFI network is extended by means of the WIFI extender interface, this allows the ventilation unit to be controlled at extended distances from the ventilation unit.

In some embodiments, the WIFI extender interface is arranged to be part of a mesh network, e.g. by operating as a node in such mesh network.

The controller may be operatively connected to one or more closure inputs for connection to outputs from any given wired device, e.g. AC1 sensors, AC2 sensors, motion detectors, home security systems, home automation systems, for receiving signals from said wired devices. For example, this allows wired security systems and home automation systems to control (on/off/auto) the vent with their respective contact closure outputs.

In some embodiments, the contact closure inputs may be arranged to allow reading the current status therefrom. Hence, a security system may thus read the status of a connected air particle sensor, e.g. smoke detector, and/or connected motion or occupancy detector with those contact closure inputs, or any other device connected to the closure inputs.

In an embodiment, the controller comprises a wired communication interface for receiving from and sending data to a connected wireless device via wire.

In an embodiment, the controller comprises an Internet-of-things (loT) interface allowing the controller to transfer data over a network without requiring human-to-human or human-to- computer interaction. The loT interface allows for machine-to-machine communication between the ventilation unit and one or more Internet-of-Things (loT) devices. For example, the loT interface may be arranged to request and receive software updates for the ventilation unit or any connected devices via Over-The-Air-programming (OTA) from one or more external devices over the Internet. The controller may further be arranged to connect to a home automation system via contact closure inputs or a local area network (LAN) application program interface (API). The API enables servers, e.g. servers on the same LAN or servers anywhere on the web, computers, and Home Automation hubs connected to the controller to control the ventilation unit (e.g. on/off/auto).

The controller may further comprise a second interface for receiving and transmitting information from/to and an application (app) accessible by a user. The information received and transmitted by the second interface may be information including the TAC parameter or TAC level, the AC1 level, the AC2 level, ventilation unit control settings, operation mode settings of the ventilation unit including any associated operation parameters, or operation parameters of the external air treatment unit. The second interface allows a user to monitor the operation of the ventilation unit, including any parameter levels, and to control the operation of the ventilation unit from the app installed e.g. on a smart phone or a tablet. According to some embodiments, the controller is arranged to monitor a number of progress parameters and/or user setting parameters to decide whether or not to update the current fan settings and/or update the control signal to the external air treatment unit.

Example progress parameters could be any associated parameters mentioned herein, including current/historic AC1 level, current/historic AC2 level, current/historic TAC level(s), current/historic AC2 level-to-TAC level approach rate (i.e. how fast the AC2 is approaching the TAC level), current/historic difference between TAC level - AC2 level, current/historic difference between TAC level - AC1 level, or current/historic difference between AC2 level - AC1 level or the absolute values of the associated differences.

It should be appreciated that in some embodiments, more than one TAC level may be accessed, e.g. one TAC parameter relating to temperature and another TAC parameter relating to humidity. The monitoring parameters may thus contain one or more TAC levels, one or more AC1 levels, and one or more AC2 levels whereby the controller is arranged to update fan or external air treatment unit settings based at least on the one or more TAC levels. For example, one TAC level may be set to 20°C, and a further TAC level may be set to 70%rh and the controller is arranged to update control settings based on the monitoring.

Example user setting parameters may include the operation parameters of the ventilation unit, e.g. the flow rate of the ventilation unit. It could also refer to a preferred operation mode of operation of the ventilation unit associated with the set speed (volumetric flow rate) of the fan, e.g. from silent mode (low fan speed and volumetric flow rate) to powerful mode (high fan speed and volumetric flow rate). For example, the operation parameter may also include an ideal fan speed that is preferred for operation during at least some type of air conditions, e.g. adverse air condition, non-worsening air condition, positive air conditions (where the AC1 level is such that it will bring AC2 level closer to TAC level when the ambient air is introduced into the indoor space), or target air conditions (when the AC2 level equals TAC level). The operation of the ventilation unit may also be related to a level of priority between forced ventilation vs the rate of reaching the TAC level which is especially relevant in adverse air conditions. A further operation parameter of the ventilation unit may be referring to a maximum allowed TAC/AC2 difference.

Updating the control signal to the external air treatment unit

In an embodiment, the controller 14 is arranged to update the control signal of the external air treatment unit with at least one updated operation setting parameter based on at least one of: the monitoring of the progress parameters and/or user setting parameters, the current fan settings of the ventilation unit, the available controllable operation parameter(s) of the external air treatment unit, and a current operation setting parameter of the external air treatment unit.

In an embodiment, the controller 14 is arranged to update the control signal of the external air treatment unit with at least one updated operation setting parameter being incrementally increased or decreased from a current operation setting parameter of the external air treatment unit by considering at least the monitoring of the progress parameters and/or user setting parameters, or the current operation parameter(s) of the external air treatment unit.

Examples of available controllable operation parameters of the external air treatment unit may be any operation parameters controllable, e.g. temperature range, target temperature, air heating modes, air cooling modes, air drying modes, relative humidity setting, air swing settings, fan settings available for the external air treatment unit, etc.

In some embodiments, the controller is arranged to access the operation parameters of the external air treatment unit by accessing (e.g. via a user interface or an application) the model number of the particular air treatment unit and download the operation parameters available from the Internet or access said parameters from a look-up table readily stored in the memory of the controller. If the external heat treatment unit has an loT interface, the controller 14 may be arranged to access the operating parameters of the external air treatment unit automatically.

Alternatively, or additionally, operation parameters available for a number of publicly available external air treatment units may be stored per default in the memory of the controller.

In an embodiment, the controller is arranged to connect to an Internet Protocol (IP) and/or Infrared (IR) device. The IP and that may be integral to the ventilation unit be any IP or IR device able to be connected to the wireless communication interface, the wired communication interface, the loT interface or the second interface of the controller. Using a connected IP or IR device, the controller is arranged to register IP/IR commands from the conventional remote control of the external air treatment unit (or optionally any other IP/IR controllable device), to allow for controlling the external air treatment unit e.g. via the connected IP and/or IR device. Hence, the controller may control room temperature by activating and deactivating the formerly unscheduled air conditioner based on the AC2 sensors of the indoor space. In some embodiments, a user may input a calendar schedule of desired temperature levels, e.g. TAC levels, of the indoor space via the associated app and the second interface. Based on the schedule the controller is arranged to output IP/IR signals, e.g. via the IP and/or IP device to the air treatment unit to control the external air treatment unit accordingly. Hence, the ventilation unit of some embodiments may be used as scheduler of the existing air treatment unit. Based on the scheduled TAC levels the controller is arranged to control the operation of the fan accordingly, due to described favourable, unfavourable or non-worsening conditions disclosed herein.

In an embodiment the controller 14 is arranged to access information about more than one TAC level, i.e. one relating to temperature and one relating to relative humidity, and

Updating the current fan settings

In an embodiment, the controller 14 is arranged to update the fan settings of the fan 13 and control the fan 13 with the updated fan settings based on: the monitoring of the progress parameters and/or user setting parameters, the current operation parameter(s) of the external air treatment unit, the available controllable operation parameter(s) of the external air treatment unit, and a current fan setting parameter of the fan 13.

In an embodiment, the controller 14 is arranged to update the fan settings by incrementally increasing or decreasing the current fan setting by considering at least the monitoring of the progress parameters and/or user setting parameters and the current operation parameter(s) of the external air treatment unit.

As mentioned above the controller may be arranged to update the fan settings, by a programmable increment or to a certain programmable setting level, based on receiving a signal from a motion detector operatively connected to the controller. This allows for controlling the fan to operate at relatively lower speed setting, e.g. silent mode setting, when an object like a person is present in the indoor space.

It also allows for controlling the fan at a relatively higher fan speed setting, or the original speed setting, when a moving object is not present in the indoor space or when a set time has expired after a moving object was detected by the motion detector.

Deactivation of the fan

In some embodiments, the controller 14 is arranged to deactivate the fan.

The deactivation of the fan 13 may e.g. be due to a user setting containing information to shut the fan 13 off, e.g. an updated user setting or when a scheduled activation period is over.

The controller 14 may also be arranged to deactivate the fan 13 when the AC2 level does not approach the TAC level, despite minimum fan speed settings and updated control signals external heat treatment unit settings to bring the AC2 level closer to the TAC level. In some embodiments, the controller 14 is arranged to deactivate the fan 13 under adverse air conditions when the absolute value of the difference between the TAC level and the AC2 level meets a threshold. Hence, if the difference between the AC2 level and the TAC level is too large, then the controller may be arranged to deactivate the fan. This will allow the AC2 level to approach the TAC level by the controller controlling the external air treatment unit. The controller 14 may be arranged to re-activate the fan 13 when the threshold is no longer met.

In some embodiments, the controller 14 is arranged to deactivate the fan 13 under neutral air conditions when the absolute value of the difference between the TAC level and the AC2 level meets a threshold. Hence, if the difference between the AC2 level and the TAC level is too large, then the controller may be arranged to deactivate the fan. This will allow the AC2 level to approach the TAC level by the controller controlling the external air treatment unit. The controller 14 may be arranged to re-activate the fan 13 when the threshold is no longer met.

The air particle sensor may in some embodiments be of a particulate matter sensor type arranged to detect smoke associated with a fire. The controller may be arranged to automatically deactivate the fan 13 based on information from such an air particle sensor or optionally any other fire or smoke detector when operatively coupled to the controller to prevent accelerating the spread of fire. In an embodiment, the controller is arranged with a microphone to monitoring a common frequency of audible fire and/or smoke alarms, and when such audible fire alarm is detected, the controller deactivates the fan. Optionally, wireless or wired fire alarms may be connected to the controller for providing an electrical signal to the controller triggering deactivation of the fan.

Filter

In some embodiments, a filter 14 is provided in the ventilation unit 10 to filter the ambient air drawn in through the inlet 11 before expelling through the outlet 12. The filter may be any filter suitable for filtering the ambient air before introducing the ambient air into the indoor space, e.g. a Lanaco filter, 3M™ filter or any other filter suitable for this purpose.

Status indicators

In an embodiment, the ventilation further comprises one or more visual status indicators, e.g. Light Emitting Diodes (LEDs), indicating the status of operation of the ventilation unit. The controller may be arranged to allow activating (turning ON) and/or disabling (e.g. turning OFF) the visual status indicator(s), based on input received via the second interface from a user operating the associated app. This allows a user to disable the status indicator(s) to keep the level of lighting in the indoor space low.

External air treatment unit The external air treatment unit may e.g. be a heat pump, e.g. a residential heat pump, air source heat pump or a water source heat pump, or air conditioning unit, air purifier unit.

Alternatively, or additionally, the external air treatment unit may be an HVAC system, e.g. a ducted HVAC system with built in heating or heat exchange capabilities. This would be especially advantageous when mounting the herein disclosed ventilation unit 10 in indoor spaces provided with no HVAC system, but which are neighbouring indoor spaces provided with an HVAC system.

According to an embodiment, the fan 13 of the ventilation unit 10 is distinct from the fan of the external air treatment unit 300.

Further, the ventilation unit 10 may be distinct from the external air treatment unit 300. As shown with reference to Figs 1, 2, 4 and 5 the housing 15 of the ventilation unit may comprise a circumferential lip 151 arranged to cover the flow passage of the structure, e.g. inner ceiling or inner walls into which the ventilation unit is installed in use. In some embodiments, the lip 151 comprises means for fastening the ventilation unit to the structure. In some embodiments, the lip is arranged to engage with the structure, in use. The insert part of the housing 15 is arranged to fit into the flow passage of the structure, in use. The insert part of the housing 15 has a smaller diameter (or dimension) than that of the circumferential lip 151 to allow for the insert part to be inserted into the flow passage of the structure while the circumferential lip 151 engages with the exterior peripheral surfaces around the flow passage of the structure during installation. The circumferential lip 151 thus protrude away from the boundary of the structure, and into the indoor space, when installed.

The housing 15 may optionally further comprise a perforated cover 16 part enclosing the fan 13 and the inlet side 11 of the ventilation unit, while allowing air to pass through the perforations provided in said cover, see Fig. 1.

Extraction Fan Configuration

Although the present invention has been described with reference to providing forced ventilation from an ambient area into an indoor space, it should be appreciated that the ventilation unit disclosed herein may be used as an extraction fan as well.

With reference to Figs 1 and 2 it may be observed that the fan 13 is separately mounted into a seat or recess of the housing or insert 15 at the top of the housing, i.e. the end of the housing closest to the ambient area when installed. Like most conventional fans the fan 13 may be of a type that is arranged to draw in air from an upstream side of the fan and expel said air at a downstream side of the fan. With reference to Fig. 2 the fan 13 is mounted so as to allow air from an ambient area (from above in Fig. 2) 203, upstream the fan, to be expelled into an indoor space 202 (below in Fig. 2) downstream the fan. Hence, in this configuration the outlet 12 side of the ventilation unit acts as a downstream side, whereas the inlet 11 side of the ventilation unit acts as an upstream side in the configuration of Figs 1 and 2. With reference to Fig. 2 the external air treatment unit 300 may be installed to directly treat the air of the indoor space 202, as opposed to treating the ambient air of the ambient area 203. Hence, in this configuration the ambient air drawn through the ventilation unit 10 is mixed with the indoor space air when expelled into the indoor space as the fan is activated. When in operation the air treatment unit 300 thus treats the mixed indoor spaced air to bring the AC2 level closer to the TAC level or optionally to maintain the AC2 level constant.

As may be observed from Fig. 2 the fan 13 of the ventilation unit 10 is not provided inline with the external air treatment unit 300. Further, it introduces air from the ambient area 203 being separate from the indoor space 202 for the ambient air to mix with the existing indoor space air. In this way, the fan 13 of the ventilation unit 10 is arranged distinct from the external air treatment unit. However, as will be further elucidated below the ambient area need not be separate from the indoor space in some embodiments.

The ventilation unit 10 may be installed so that the outlet 12 of the ventilation unit faces the external air treatment unit 300. Accordingly, the outlet 12 of the ventilation unit 10 may be arranged closer to the external air treatment unit 300 than that of the inlet 11 of the ventilation unit 10.

In some embodiments, the ventilation unit 10 may be installed so that the inlet 11 of the ventilation unit faces the external air treatment unit 300. Accordingly, the inlet 11 of the ventilation unit 10 may be arranged closer to the external air treatment unit 300 than that of the outlet 12 of the ventilation unit 10. Such an embodiment may be advantageous when the ventilation unit is installed between two indoor spaces, such as an inner wall or inner ceiling. Fig. 5 shows such a configuration.

According to one alternative embodiment, with reference to Figs 4 and 5 by mounting the fan 13 up-side-down in relation to its configuration in Figs 1 and 2 and into the seat or recess of the housing or insert, the ventilation unit is converted into an extraction fan now drawing air from the indoor space 202 and expelling said air into the ambient area 203. This extraction fan configuration may be advantageous in multi storey homes, where it is desired to provide forced ventilation of air from the one storey to the next above, or when the ventilation unit is installed between two adjacent indoor spaces with one acting as the ambient area. For example, the ventilation unit used as an extraction fan may advantageously be mounted in rooms having an external heat source, e.g. wood burner or heat pump to allow for distributing the heat from the room having the heat source to adjacent rooms.

It should be appreciated that when the ventilation unit is assembled as an extraction fan all of the functionality of the controller still remains available. Depending on the way fan is mounted one side of the ventilation unit will act as a downstream side or an upstream side.

When converting the ventilation unit from forced ventilation configuration to extraction fan configuration, the original "ambient area/upstream" AC1 inputs or settings or levels, e.g. AC1 inputs, parameter, levels now form the "indoor space/downstream" inputs, while the original "indoor space/downstream" inputs or settings, e.g. AC2 inputs, parameters, levels, and TAC levels form the "ambient area/upstream" inputs.

Like the forced ventilation configuration of Fig. 2, in the extraction fan configuration the external air treatment unit 300 may be installed to directly treat the air of the indoor space 202, as opposed to treating the ambient air of the ambient area 203. However, in this configuration what used to be an outlet 12 of the ventilation unit 10 now acts as input 11. In this configuration the air treated indoor space air is drawn through the ventilation unit 10 via the upstream side inlet 11 and expelled through the downstream outlet 12 into the ambient area 203, thus mixing the treated indoor space air with the ambient air of the ambient area 202. When in operation the controller may be arranged to control the external air treatment unit bring the AC2 level of the ambient area 203 closer to the TAC level.

As may be observed from Fig. 5 the fan 13 of the ventilation unit 10 is not provided inline with the external air treatment unit. Further, it introduces air from the air treated indoor space area, being separate from the ambient area for, to mix with the ambient air. In this way, the fan 13 of the ventilation unit 10 is arranged distinct from the external air treatment unit.

The ventilation unit 10 may thus be installed so that the inlet 11 of the ventilation unit faces the external air treatment unit. Accordingly, the inlet 11 of the ventilation unit 10 may be arranged closer to the external air treatment unit than that of the outlet 12 of the ventilation unit 10.

In some embodiments, the "ambient area" as referred to herein may relate to a further "indoor space". As such the ventilation unit 10 may be arranged in an interior wall or inner ceiling and the like for providing forced ventilation between a first indoor space and a second indoor space. The first indoor space may be arranged in communication with the upstream side of the ventilation unit from which air is drawn into the ventilation unit via the inlet 11, while the second indoor space may be arranged in communication with the downstream side of the ventilation unit into which the drawn in air from the first indoor space is expelled via the outlet 12.

Hence, according to some embodiments the "ambient area" may be a first indoor space or upstream indoor space, and the "indoor space" as described herein may relate to a second indoor space or downstream indoor space. Depending on the space the external air treatment unit is installed, the controller of the unit may be setup accordingly in either forced ventilation or extraction configuration.

Optionally, a TAC level may be set for both the upstream side the downstream area. Under such conditions, the controller may be arranged to prioritize meeting the TAC level of the downstream side by controlling the fan to draw air from the upstream side while given the favouring, non-worsening, or unfavourable conditions control the external air treatment unit as further elucidated herein.

As an example, lets imagine the ventilation unit in extraction fan configuration mounted in an inner wall between two adjacent rooms, with the upstream side in one of the rooms having an external air treatment unit is installed. Assume that the TACdownstream level in the adjacent room is set to 20°C by a user using the associated app, while the TAC_upstream level is set to 22°C. The current ACl_uPstream level is 21°C and the current AC2 _Ownstream level is 18°C. Downstream conditions are favourable since by operating the fan the AC2 _Ownstream level will be brought towards the TACdownstream- The controller is thus arranged to activate the fan. But while operating the fan and increasing the temperature in the downstream side, heat will be forced out from the upstream side, whereby a temperature drop is expected. Hence, conditions for operating the fan are unfavourable in the upstream side, since the ACl_uPstream level, currently at 21°C is likely to drop as a result of the heat transfer into the colder downstream side, thereby moving further away from the TAC_upstream level of 22°C. Based on identifying the unfavourable condition on the upstream side the controller is arranged control the external air treatment unit to bring the ACl_uPstream level closer to the TAC_upstream level based on the activation of the fan.

Hence, it should be appreciated that the ventilation unit may be used as a forced ventilation unit, an extraction fan unit and/or heat transfer unit. Also, the ventilation unit is capable of controlling the fan to meet target air condition parameters on the upstream/downstream side or both of the upstream and downstream side by activation of the fan, and operating the external air treatment unit.

In some embodiments, the controller 14 of the ventilation unit 10 is arranged to control the operation mode of more than one external air treatment unit. For example, a first external air treatment unit 300 may be arranged to treat the air on the upstream side of the ventilation unit 10, e.g. in an ambient area or first indoor space, while a second external air treatment unit may be arranged to treat the air on the downstream side of the ventilation unit, e.g. in the indoor space or second indoor space.

In an embodiment, with reference to Figure 3 a method 20 of controlling the operation of a ventilation unit 10 providing forced ventilation of ambient air into an indoor space bounded by a structure, e.g. an inner wall, outer wall, or inner ceiling, when the ventilation unit 10 is installed in a flow passage provided through said structure is provided. The ventilation unit 10 comprises an inlet 11, an outlet 12 providing access to the indoor space, in use, and a fan 13 arranged to draw ambient air into the ventilation unit via the inlet 11 and expel said air through the outlet 12, the method comprising accessing (21), by a controller 14, information associated with a target air condition (TAC) parameter of air in the indoor space, and determining a level (TAC level) of the TAC parameter, accessing (22), by the controller 14, information from at least one first sensor arranged to sense a first air condition parameter (AC1) associated with the ambient air, in use, and determining a level (AC1 level) of the AC1 parameter, accessing (23), by the controller 14, information from at least one second sensor arranged to sense a second air condition parameter (AC2) associated with air in the indoor space, in use, and determining a level (AC2 level) of the AC2 parameter, activating (24) the fan 13 when:

(a) the TAC level equals the AC2 level while the AC1 level differs from the TAC level; or

(b) the TAC level differs from the AC2 level to an extent while the TAC level differs from the AC1 level to an even greater extent while the AC1 level and AC2 level are either both higher or both lower than the TAC level, or

(c) the TAC level differs from the AC2 level while the AC1 level is equal to the AC2 level, and sending (25) a control signal to an external air treatment unit 300 fluidly connected to the indoor space for controlling the operation mode of said external air treatment unit to bring the AC2 level closer to the TAC level based on the activation of the fan.

Figure 6 shows an alternative representation of the method of Figure 2. The method 600 of Figure 6 comprises receiving 601 user/app settings information associated with the operation settings of the ventilation unit, ventilation modes, external air treatment unit parameters etc. The step of 602 covers the steps 21 to 23 of the method 20 of Fig. 2. The method 600 further comprises determining the current air conditions in 603. The method 600 further comprises activating 604 the fan based on a number of parameters, similar to step 24 of method 20. Further, step 605 is similar to step 25 of method 20.

Claims

1. A ventilation unit for providing forced ventilation of ambient air into an indoor space bounded by a structure, e.g. an inner wall, outer wall, or inner ceiling, when installed in a flow passage provided through said structure, the ventilation unit comprising: an inlet, an outlet providing access to the indoor space, in use, a fan arranged to draw ambient air into the ventilation unit via the inlet and expel air through the outlet, a controller arranged to: access information associated with a target air condition (TAC) parameter of the indoor space air, and determine a TAC level of the associated TAC parameter; access information from at least one first sensor arranged to sense a first air condition (AC1) parameter associated with the ambient air, in use, and determine an AC1 level of the associated AC1 parameter; access information from at least one second sensor arranged to sense a second air condition (AC2) parameter associated with air in the indoor space, in use, and determine an AC2 level of the associated AC2 parameter; activate the fan when:

(b) the TAC level differs from the AC2 level to an extent while the TAC level differs from the AC1 level to an even greater extent, or

(c) the TAC level differs from the AC2 level while the AC1 level is equal to the AC2 level, and send a control signal to an external air treatment unit fluidly connected to the indoor space for controlling an operation mode of said external air treatment unit to bring the AC2 level closer to the TAC level based on the activation of the fan.

2. The ventilation unit according to claim 1, further comprising the at least one first sensor.

3. The ventilation unit according to claim 1 or 2, further comprising the at least one second sensor.

4. The ventilation unit according to any of the preceding claims, wherein the TAC level is lower than the AC2 level while the AC2 level is lower than or equal to the AC1 level.

5. The ventilation unit according to any of the preceding claims, wherein the TAC level is higher than the AC2 level while the AC2 level is higher than or equal to the AC1 level.

6. The ventilation unit according to any of the preceding claims, wherein one of the at least one first sensor is a temperature sensor, wherein the associated AC1 parameter relates to ambient air temperature.

7. The ventilation unit according to any of the preceding claims, wherein one of the at least one first sensor is a humidity sensor, relative humidity sensor, or absolute humidity sensor, wherein the associated AC1 parameter relates to ambient air humidity.

8. The ventilation unit according to any of the preceding claims, wherein one of the at least one first sensor is an air particle sensor, wherein the associated AC1 parameter relates to ambient air particle content.

9. The ventilation unit according any of the preceding claims, wherein one or more of the at least one first sensor is/are arranged in the vicinity of the inlet.

10. The ventilation unit according to any of the preceding claims, wherein one of the at least one second sensor is a temperature sensor, wherein the associated AC2 parameter relates to air temperature.

11. The ventilation unit according to any of the preceding claims, wherein one of the at least one second sensor is a humidity sensor, relative humidity sensor, or absolute humidity sensor, wherein the associated AC2 parameter relates to air humidity.

12. The ventilation unit according to any of the preceding claims, wherein one of the at least one second sensor is an air particle sensor, wherein the associated AC2 parameter relates to air particle content.

13. The ventilation unit according to any of the preceding claims, wherein one or more of the at least one second sensor is/are arranged in the vicinity of the outlet.

14. The ventilation unit according to any of the preceding claims, wherein one or more of the at least one first sensor is an external sensor or integral with the ventilation unit.

15. The ventilation unit according to any of the preceding claims, wherein one or more of the at least one second sensor is an external sensor or integral with the ventilation unit.

16 The ventilation unit according to claims 14 or 15, wherein the external sensor is a wired or wireless sensor.

17. The ventilation unit according to any of the preceding claims, wherein the TAC parameter relates to air temperature, air humidity, relative air humidity, absolute air humidity, or air particle content.

18. The ventilation unit according to any of the preceding claims, wherein the external air treatment unit is a heat pump, e.g. a residential heat pump, air source heat pump or a water source heat pump, or air conditioning unit, air purifier unit.

19. The ventilation unit according to any of the preceding claims, wherein the at least one second sensor is arranged to sense an AC2 parameter of the air of the indoor space, in use.

20. The ventilation unit according to any of the preceding claims, wherein the control unit is arranged to derive at least one setting parameter to be included in the control signal based on at least one of: the dimensions of the indoor space, at least one AC1 parameter, at least one AC2 parameter, at least one TAC parameter, an operation parameter of the ventilation unit, and an operation parameter of the external air treatment unit.

21. The ventilation unit according to any of the preceding claims, wherein the controller comprises a first interface for machine-to-machine communication between the ventilation unit and one or more Internet-of-Things (loT) devices.

22. The ventilation unit according to claim 21, wherein the first interface is arranged to receive software updates via Over-The-Air-programming (OTA) from one or more devices over the Internet.

23. The ventilation unit according to any of the preceding claims, wherein the controller comprises a second interface for receiving and transmitting information from/to and an application (app) accessible by a user.

24. The ventilation unit according to any of the preceding claims, wherein information received by the second interface is information relating to: the TAC parameter, ventilation unit control settings, operation mode settings of the ventilation unit, or operation parameters of the external air treatment unit.

25. The ventilation unit according to any of the preceding claims, wherein the controller is arranged to connect to a home automation system via contact closure inputs or a local area network (LAN) application program interface (API).

26. The ventilation unit according to claim 8 or 12 or any claim dependent thereon, wherein the controller is arranged to deactivate the fan when a level of the air particle content exceeds a safety threshold.

27. The ventilation unit according to any of the preceding claims, wherein the controller is arranged to determine that an adverse air condition exists when the ambient air with the associated AC1 level if introduced into the indoor space would result in moving the AC2 level further away from the TAC level, and activate the fan subject to the determined adverse air condition.

28. The ventilation unit according to claim 27, wherein the controller is arranged to determine that an adverse air condition exists when the TAC level equals the AC2 level while the AC1 level differs from the TAC level.

29. The ventilation unit according to claim 27 or 28, wherein the controller is arranged to determine that an adverse air condition exists when the TAC level differs from the AC2 level to an extent while the TAC level differs from the AC1 level to an even greater extent, while the AC1 level and AC2 levels are both higher or lower than the TAC level.

30. The ventilation unit according to any one of the preceding claims, further comprising a motion detector or an occupancy sensor for detecting the motion or presence of an object.

31. The ventilation unit according to claim 30, wherein the controller is arranged to execute a specific task based on receiving a signal from the motion detector, the specific task being selected from at least one of the following: to lower the fan speed, by a certain increment or to a certain speed setting, to reducing the noise levels upon receiving a signal from the motion detector relating to a detected presence of a moving object, or to increase the fan speed to an original setting, by a certain increment or to a certain setting speed, to increase the forced ventilation when an object is no longer detected by the motion detector, when a predetermined time period has lapsed from when the controller last received a signal from the motion detector relating to a detected presence of a moving object.

32. The ventilation unit according to claim 30 or 31, wherein the controller is arranged to connect to an existing home security systems to allow the motion detector to act as a wired motion detector, when operatively coupled to such home security system.

33. The ventilation unit according to any one of the preceding claims, further comprising a Internet Protocol (IP) or Infrared (IR) device operatively connected to the controller, and arranged to register any IP/IR commands from a conventional remote control associated with the external air treatment unit, and wherein the controller is arranged to send IP/IR commands to the external air treatment unit via the IP or IR device for controlling an operation mode of said external air treatment unit.

34. The ventilation unit according to claim 23 or any claim dependent thereon, wherein the controller is arranged to receive a calendar schedule of desired target air condition parameter levels via the second interface and the associated app, and control the external air treatment unit based on the received calendar schedule.

35. The ventilation unit according to claim 23 or any claim dependent thereon, further comprising one or more visual status indicators, wherein the controller is arranged to allow activating (turning ON) and/or disabling (e.g. turning OFF) the visual status indicator(s), based on input received via the second interface from a user operating the associated app.

36. The ventilation unit according to any of the preceding claims, arranged to operate in a MIN Auto Drying mode, MAX Auto Drying mode, or Moderate Auto Drying mode.

37. The ventilation unit according to any of the preceding claims, further comprising a WIFI extender interface arranged to create an extended WIFI network surrounding the ventilation unit and/or be part of a mesh network.

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38. The ventilation unit according to any of the preceding claims, wherein the controller is arranged to control the operation mode of the external air treatment unit in parallel with the activated fan.

39. A system for providing forced ventilation of ambient air into an indoor space bounded by a structure, e.g. an inner wall, outer wall, or inner ceiling, when installed in a flow passage provided through said structure, the system comprising: the ventilation unit according to any one of the claims 1 to 38, and an external air treatment unit fluidly connected to the indoor space, in use.

40. Method of controlling the operation of a ventilation unit providing forced ventilation of ambient air into an indoor space bounded by a structure, e.g. an inner wall, outer wall, or inner ceiling, when the ventilation unit is installed in a flow passage provided through said structure, the ventilation unit comprising an inlet, an outlet providing access to the indoor space, in use, and a fan arranged to draw ambient air into the ventilation unit via the inlet and expel said air through the outlet, the method comprising accessing, by the controller, information associated with a target air condition (TAC) parameter of air in the indoor space, and determining a level (TAC level) of the TAC parameter, accessing, by the controller, information from at least one first sensor arranged to sense a first air condition parameter (AC1) associated with the ambient air, in use, and determining a level (AC1 level) of the AC1 parameter, accessing, by the controller, information from at least one second sensor arranged to sense a second air condition parameter (AC2) associated with air in the indoor space, in use, and determining a level (AC2 level) of the AC2 parameter, activating the fan when:

(c) the TAC level differs from the AC2 level while the AC1 level is equal to the AC2 level, and sending a control signal to an external air treatment unit fluidly connected to the indoor space for controlling an operation mode of said external air treatment unit to bring the AC2 level closer to the TAC level based on the activation of the fan.

41. Method of controlling the operation of a ventilation unit providing forced ventilation of ambient air into an indoor space bounded by a structure, e.g. an inner wall, outer wall, or inner

32 ceiling, when the ventilation unit is installed in a flow passage provided through said structure, the ventilation unit comprising an inlet, an outlet providing access to the indoor space, in use, and a fan arranged to draw ambient air into the ventilation unit via the inlet and expel said air through the outlet, the method comprising receiving user/app settings information associated with the operation settings of the ventilation unit, accessing, by the controller, information associated with a target air condition (TAC) parameter of air in the indoor space, and determining a level (TAC level) of the TAC parameter, information from at least one first sensor arranged to sense a first air condition parameter (AC1) associated with the ambient air, in use, and determining a level (AC1 level) of the AC1 parameter, and information from at least one second sensor arranged to sense a second air condition parameter (AC2) associated with air in the indoor space, in use, and determining a level (AC2 level) of the AC2 parameter, determining whether the accessed information is indicative of at least one of adverse air conditions or neutral or non-worsening air conditions, activating the fan:

(a) under adverse air conditions when the TAC level equals the AC2 level while the AC1 level differs from the TAC level; or

(b) under adverse air conditions when the TAC level differs from the AC2 level to an extent while the TAC level differs from the AC1 level to an even greater extent while the AC1 level and AC2 level are either both higher or both lower than the TAC level, or

(c) under neutral or non-worsening conditions when the TAC level differs from the AC2 level while the AC1 level is equal to the AC2 level, and sending a control signal to an external air treatment unit fluidly connected to the indoor space for controlling an operation mode of said external air treatment unit to bring the AC2 level closer to the TAC level based on the activation of the fan.

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