AIR TREATMENT UNIT

Abstract

An air treatment unit 10 for attachment to a fan coil unit 12 for treating air from an indoor setting, the air treatment unit 10 including: an inlet 14 for connection to a ducting system that receives indoor air; a treatment volume 22 for receiving air flow from the inlet 14; a UV-C light source 24 within the treatment volume 22 for exposing the air in the treatment volume 22 to UV-C radiation; and an outlet 16 for discharge of treated air to the fan coil unit 12, the outlet 16 is configured for connection to an inlet plenum 18 of the fan coil unit 12.

Claims

1. An air treatment unit for attachment to a fan coil unit for treating air from an indoor setting, wherein the air treatment unit comprises: an inlet for connection to a ducting system that receives indoor air; a treatment volume for receiving air flow from the inlet; a UV-C light source within the treatment volume for exposing the air in the treatment volume to UV-C radiation; and an outlet for discharge of treated air to the fan coil unit, wherein the outlet is configured for connection to an inlet plenum of the fan coil unit.

2. An air treatment unit as claimed in claim 1, wherein the treatment unit comprises a UV-C light source of suitable intensity for the intended air flow rate of the fan coil unit to provide a minimum dosage level of 25 J/m2 of UV-C for the air in the treatment volume.

3. An air treatment unit as claimed in claim 1, wherein the UV-C light source is configured to provide a minimum dose of 25 J/m2 at an air flow rate in the range 200-400 m3/h, optionally 250-350 m3/h, such as an air flow rate of about 300 m3/h.

4. An air treatment unit as claimed in claim 1, wherein the the air treatment unit comprises a housing with openings for the inlet and the outlet, wherein the treatment volume is contained within the housing.

5. An air treatment unit as claimed in claim 4, wherein the housing comprises a maintenance door for providing access within the treatment volume; and wherein the maintenance door is provided with a safety cut off configured to disable the UV-C light source when the maintenance door is used.

6. An air treatment unit as claimed in claim 5, wherein the use of the maintenance door comprises opening of the door or of a latch of the door, and/or wherein use of the maintenance door comprises unlocking of a lock of the door; and optionally wherein the safety cut off is arranged to re-enable the UV-C light source when the door is no longer in use.

7. An air treatment unit as claimed in claim 4, wherein the treatment unit comprises UV-C shielding around the treatment volume for preventing the UV-C radiation from escaping the housing, and wherein in the air flow path the UV-C shielding comprises openings in order to permit air flow but block line of sight for the UV-C radiation.

8. An air treatment unit as claimed in claim 4, wherein the housing includes an inspection opening for allowing a person to see, from the outside, if the UV-C light source is active; and wherein the inspection opening is configured to allow transmission of visible light but to block UV-C light.

9. An air treatment unit as claimed in claim 1, wherein the air treatment unit is configured to detect occupancy of the indoor space in order to deactivate the UV-C light source when the indoor space is unoccupied and/or to only permit it to activate when the indoor space is occupied; and optionally wherein the air treatment unit comprises a CO2 sensor for determining if the indoor space is occupied.

10. An air treatment unit as claimed in claim 1, wherein the air treatment unit is configured to activate the UV-C light source in response to operation of the fan coil unit, such as in response to operation of the fan thereof, optionally wherein the UV-C light source is activated at a set time period after the fan of the fan coil unit is activated, for example 5 minutes.

11. An air treatment unit as claimed in claim 10, wherein the air treatment unit is configured to interact with a control system of the fan coil unit to enable it to receive a signal indicating that the fan coil unit is operating.

12. A system comprising the air treatment unit of claim 1 and a fan coil unit, wherein the outlet of the air treatment unit is coupled to the inlet plenum of the fan coil unit.

13. A system as claimed in claim 12, wherein the fan coil unit has a controller having a dedicated output for control of the UV-C light source, and optionally the fan coil unit provides input to the air treatment unit regarding occupancy of the indoor space.

14. A method of installation of an air treatment unit as claimed in claim 1, the method comprising: providing the air treatment unit; and fitting the outlet of the air treatment unit to the inlet plenum of a fan coil unit.

15. A method of treating air from an indoor setting comprising: using the treatment unit of claim 1 and operating the UV-C light source to expose the air to UV-C radiation.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The present invention will now be described, by way of example only, with reference to the accompanying drawings, in which:

[0023] FIG. 1 shows an air treatment unit connected to a fan coil unit,

[0024] FIG. 2 shows the air treatment unit of FIG. 1 without the fan coil unit and with housing parts removed to show internal detail,

[0025] FIG. 3 is another view of the air treatment unit of FIG. 1 with a lower maintenance door removed, and

[0026] FIG. 4 shows another example of an air treatment unit with a different inlet configuration.

DETAILED DESCRIPTION OF THE INVENTION

[0027] FIG. 1 shows an air treatment unit 10 connected to a fan coil unit 12. This can be done as a modification to a system with a pre-existing fan coil unit 12 to add an added air treatment capability, or it can be done along with installation of the fan coil unit 12. The air treatment unit 10 is for providing UV-C radiation treatment of the air in order to deactivate the DNA of viruses, as well as giving other sterilisation effects. In this example the treatment unit is advantageously configured in order to provide a minimum dosage level of 25 J/m2 of UV-C for the air based on the expected air flow rate of the fan coil unit 12.

[0028] The air treatment unit includes an inlet 14 for connection to a ducting system, and an outlet 16 for connection to the inlet plenum 18 of the fan coil unit 12. FIGS. 2 and 3 show further detail of the inlet 14 and outlet 16 as well as added details of the air treatment features of the air treatment unit 10. In particular, an outer housing 20 of the air treatment unit 10 encloses a treatment volume 22, within which a UV-C light source 24 is provided for exposing air in the treatment volume to UV-C radiation at the required dosage. The UV-C light source 24 includes at least one UV-C lamp, e.g. an LED lamp or fluorescent tube, may produce radiation with wavelength in the range 240-280 nm or 250-260 nm, such as light at a wavelength of about 254nm. In this example the UV-C light source 24 is a mercury vapour lamp that provides radiation with 19 W UVC output..

[0029] As seen in FIGS. 2 and 3 the air treatment unit 10 includes a filter 26 adjacent the inlet 14 for removing particles from the air flowing into the unit 10. UV shielding 28 is provided at the outlet 16, to prevent UV exposure of the fan coil unit 12, and at the filter 26 to protect the filter 26 and prevent UV from being emitted into the ducting. The walls of the housing 20 also act as UV shielding elements. Thus, the UV-C radiation from the UV-C light source 24 is contained within the treatment volume 22. The air treatment unit 10 also includes control and power circuitry 30, which can include a controller for activating the UV-C light source 24 and/or ballast for the UV-C light source 24. A switch 32 is included for activating and deactivating the UV-C light source 24, which may be done under control of the controller.

[0030] The housing 20 further comprises a maintenance door 34, in this case at the bottom in the orientation shown in FIGS. 2 and 3. The maintenance door 34 is for providing access within the treatment volume 22, such as for inspection and maintenance of the UV-C light source 24, e.g. for replacement of a UV-C lamp of the UV-C light source 24. The maintenance door 34 is provided with a safety cut off configured to disable the UV-C light source 24 when the maintenance door 34 is used. In this example the safety cut off includes a door contact 36 connected to the switch 32, whereby opening of the door 34 will disable the UV-C light source 24 by action of the door contact 36 and switch 32 to disconnect the UV-C light source from its power supply.

[0031] The housing 20 may provide structural support for the various parts discussed above including the UV-C light source 24. It is supported in place by its connection at the outlet 16 to the fan coil unit plenum 18 and by its connection at the inlet 14 to the ducting system, as well as being supported by brackets 38 for mounting to a building or structures within the building. The air treatment unit 10 in this example is arranged for installation in a false ceiling of a room in a building along with the fan coil unit 12, where they form a part of the buildings HVAC system.

[0032] The air treatment unit 10 and/or the fan coil unit 12 detect occupancy of the indoor space. This allows the air treatment unit 10 to deactivate the UV-C light source 24 when the indoor space is unoccupied and/or to only permit it to activate when the indoor space is occupied. By way of example, the air treatment unit 10 or the fan coil unit 12 can comprise a CO2 sensor for determining when the indoor space is occupied. In addition, the air treatment unit 10 may be configured to activate or deactivate the UV-C light source 24 in response to the operation status of the fan coil unit 12, in particular based on operation of a fan thereof

[0033] Advantageously, the air treatment unit 10 is configured to interact with a control system of the fan coil unit 12, for example being connected to the fan coil unit 12 to enable it to receive a signal indicating that the fan coil unit 12 is operating, i.e. that the fan of the fan coil unit is running. This optionally also allows for the air treatment unit 10 to receive input from the fan coil unit control system regarding occupancy of the indoor space and/or other control inputs, such as indications of variations in air flow rate. In cases where the fan coil unit 12 can vary the air flow rate then the intensity of the UV-C light source 24 can advantageously be controlled in order to maintain a required dosage level.

[0034] It will be understood that installation of the air treatment unit 10 is simple since it is designed to fit directly to the fan coil unit 12. Installation hence comprises fitting the outlet 16 of the air treatment unit 10 to the inlet plenum 18 of the fan coil unit 12, which may already have been installed in the building. The air treatment unit 10 can be retrofitted to a pre-existing fan coil unit 12, or it may be done as a part of an installation of a bigger system, i.e. concurrent with installation of the fan coil unit 12 and/or the ducting system. The installation of the air treatment unit 10 may include calibration to set the intensity of the UV-C light source 24 based on the intended air flow rate of the fan coil unit 10, in particular in order to achieve a required dosage level of the UV-C, such as the minimum 25 J/m2 dose discussed above.

[0035] FIG. 4 shows another example of an air treatment unit 10, in this case for connection to a double ducting arrangement. This example therefore has a differing configuration for the inlet 14, but it may be otherwise similar to the air treatment unit 10 of FIGS. 1 to 3.