AN EVAPORATOR UNIT FOR AN AIR CONDITIONING SYSTEM.

Abstract

An evaporator unit for an air conditioning system 1, the unit comprising an evaporator coil 7, a sensor 12 for detecting the liquid level in a reservoir, and a pump for pumping condensate from the housing; at least one UV LED 6, 8 is arranged to radiate light onto the evaporator coil 7 and / or the sensor 12; an LED driver 13 supplies electrical power to the LEDs; an individual electrical power connection 14 can be connected to a main power source to supply main power to the pump; wherein the LED driver 13 is connected to the electrical power connection that supplies power to the pump.

Description

AN EVAPORATOR UNIT FOR AN AIR CONDITIONING SYSTEM DESCRIPTIVE MEMORANDUM The present invention relates to an evaporator unit for an air conditioning system. Air conditioning systems are well known in the art in which an evaporator unit inside a building is connected to a compressor unit that is mounted on the outside of the building. The evaporator unit can be wall- or ceiling-mounted, or it can be floor-mounted or freestanding. Such air conditioning unit systems are efficient and effective for providing cooling to an individual space (i.e., in a non-centralized air conditioning system). The evaporator unit has a wall-mountable housing that contains an evaporator coil through which a refrigerant is pumped. A fan forces airflow through the evaporator coil and out an outlet in the housing to provide a flow of cool air into the room to be cooled. Dangerous pathogens can grow on the evaporator coil and become trapped in the airflow through the evaporator unit. One known method for addressing this is the use of ultraviolet light. The use of UV lamps in this manner is known in other applications, as described, for example, in CN209763350, CN109654627, US2005 / 284167, CN201334687, CN101463616, and WO2012 / 009024. UV-C light was used in an evaporator unit. This is effective at killing 99% of viruses, bacteria, and mold. To achieve this, an array of UV-C light-emitting diodes (LEDs) is fitted, directed toward the evaporator coil and into the airflow path through the evaporator unit. These are provided as an upgrade for an existing evaporator unit. However, this creates a practical problem since air conditioning units are installed by HVAC engineers. On the other hand, LED systems require installation by an electrician. To install the LEDs, the evaporator unit needs to be provided with a second main power supply. Once an HVAC engineer has installed the evaporator, the electrician will connect the LEDs and their associated power supply. This is time-consuming and presents a logistical challenge in ensuring the right personnel are available at the right time. As a result, these systems are not currently widely used. cnr / nn / Q7n7 / B / YiAi In evaporative units, a sensor is provided in the reservoir to measure the condensate level and activate the pump to empty it. Impurities in the water can accumulate around the sensor, which can eventually cause it to become clogged and malfunction. The present invention aims to simplify this complicated process and / or solve the problem of the obstructed sensor. In accordance with the present invention, a wall-mounted evaporator unit is provided for an air conditioning system according to claim 1. The arrangement described above requires only one individual electrical connection to the main power source. This allows the air conditioning unit, the LEDs, and their power supply to be installed by a single HVAC engineer, significantly streamlining the installation process. The ease with which the present invention allows a UV LED to be incorporated into the evaporator unit means that UV LEDs can be more easily developed in areas where they have not been previously used, such as in the vicinity of the deposit sensor. The at least one LED and LED driver can be permanently installed within the unit. However, preferably, the at least one LED and LED driver are removably attached within the housing, and the electrical connection from the LED driver to the power supply for the pump is in the form of a removable plug that connects to a connector associated with the power supply for the pump. This allows the LED and LED driver to be removed from the unit and replaced for maintenance purposes, while retaining the advantage of the present invention concerning the ease of installation of the initial unit. The ease with which the present invention allows a UV LED to be incorporated into the evaporator unit means that UV LEDs can be more easily developed in areas where they have not been previously used. This forms a second aspect of the present invention, according to which there is an evaporator unit for an air conditioning system according to claim 6. As far as we know, in an evaporator unit of an air conditioning system, the use of non-chemical means to keep the residual liquid in the tank free of organic growth and other contaminants is not known in the art. The problem of such contaminants can be addressed to some extent by using a self-priming pump, such as a rotary diaphragm pump, which is capable of running dry in order to reduce the amount of water in the tank as much as possible. cnr / nn / Q7n7 / e / YiAi However, the reservoir will contain water between pump operations, and even when the pump is running, this will not remove all traces of water from the reservoir. Therefore, the best protection against contaminants is a combination of the current evaporator unit with a self-priming pump, as the UV LEDs will eliminate the small amount of contaminants that would otherwise appear on the sensor. However, in any case, there is a greater need for the present evaporator unit in a non-self-priming pump since there is always a significant amount of wastewater in the tank and the amount of contaminant is a more significant problem. An example of an evaporator unit according to the present invention will now be described with reference to the accompanying figures, where: Figure 1 is a schematic front view of a known unit with LEDs installed; Figure 2 is a similar view showing a unit in conformity with the present invention; Figure 3 is a schematic representation of a conventional power supply; Figure 4 is a similar view of the power supply according to the present invention; Figure 5 is a perspective view of a tank for use in the unit; Figure 6 is a flat view of the tank; Figure 6A is a cross-section through line AA in Figure 6; Figure 7 is a side view of a sensor module used in the tank; and Figure 8 is a top view of the sensor module. The evaporator unit, shown in Figure 1, is well known in the art and is designed to be mounted on an interior wall of a room. It is connected to an external compressor unit in the building to create a refrigeration circuit, as is well known in the art. The invention can be applied equally to a ceiling- or floor-mounted unit or to a stand-alone unit. The unit comprises a housing 1 that is wall-mountable and has a duct 2 to provide an external connection for an air inlet, the piping (not shown) for condensate discharge, and a 230-volt main power supply connected to the pump 3. The pump is configured to pump condensate from a reservoir 4 once the level exceeds a predetermined amount. The conventional unit has been installed with a first set 6 of UV-C LEDs arranged above an evaporator coil 7 and a second set 8 arranged below the evaporator coil 7. These are supplied on adhesive strips which are affixed into place inside the cnc / nn / rznz / E / YiAi housing. Ideally, the UV LED emits light with a wavelength of 100 to 280 nm, which is the germicidal part of the spectrum. More preferably, the LED emits light with a wavelength of 200 to 280 nm, as this is the most effective part of the germicidal spectrum. This is the UV-C portion of the spectrum (although some of the emitted light may have a wavelength outside this range). The wiring for this conventional unit is shown in Figure 3. As shown, the pump 3 and the LED driver 5 each have their own separate 230-volt power supplies. The first power supply 10 supplies power to the pump via live lines 10A, ground lines 10B, and neutral lines 10C. The second power supply 11 supplies power to the LED driver 5 via live lines 11A, ground lines 11B, and neutral lines 11C. This second power supply needs to be installed subsequently by a qualified electrician. LED controller 5 supplies power to LED strips 6, 8, while the pump receives signals from sensor 12 to control the flow of condensate from the reservoir. As shown in Figure 2, the present invention uses the same basic unit configuration. One of the advantages of the invention is that it can be easily incorporated into an existing unit. Instead of requiring the installation of a second 230-volt power supply, the unit now uses the existing power supply since the LED driver is integrated into the same unit 13 as the pump. As shown in Figure 4, the two power supplies 10, 11 are replaced by a single power supply 14, which has live lines 14A, ground lines 14B, and neutral lines 14C. In practice, the power supply for the LED driver is provided by a plug that connects to a corresponding connector on the pump housing or elsewhere to supplement the power supply for the LEDs 6, 8. The unit can be sold without the 6 or 8 LED strips installed. These can be installed either by an HVAC engineer at the time of installation or later. This simply requires the LED strips to be secured in place, for example, using adhesive mounts, and the LED driver to be connected. Alternatively, the LED strips and driver can be pre-installed in the unit before installation. In any case, the unit can be installed by an air conditioning engineer without the intervention of an electrician. Tank 4 and sensor 12 are shown in greater detail in Figures 5 to 8. The reservoir comprises a tank 20 closed by a lid 21. A number of components are mounted on the lid 21. This includes a sensor module 23 comprising a capacitive sensor 24 as described in W02020 / 120971 and a UVLED 25 mounted on the module next to the capacitive sensor. cnr / nn / Qznz / B / YiAi The sensor can alternatively be a thermistor or a float switch. The emitted light 26 is represented schematically in Figures 6A and 7. In practice, this is emitted with a beam angle of 120° and will therefore strike most of the sensor and the bottom of the tank 20. This serves two purposes. First, it keeps sensor 24 clean. Second, it reduces or prevents the buildup of sludge and bacteria in tank 20. The bottom of the tank can be damp and cold, causing sludge to accumulate when it's cold, which can block a pump. The sludge also dries and becomes flaky, floating in the condensate, which can again block the pump. Leading from the sensor module is a flexible cable 27 through which low-voltage power is transmitted to the sensor 24 and the UVLED 26. The flexible cable 27 terminates in a plug 28. This connects to a connector on the pump housing as described above. The pump housing may have two connectors if separate UVLEDs are also provided for the coil as described above. Therefore, the 24 sensor module is very easy to install, making it economical to introduce UVLED into an area where it has not been previously provided, thus providing the above advantages. Tank 20 has two inlets 29 through which condensate enters the tank, only one of which is used in any given application, while the other is plugged. Similarly, there is a pair of alternative outlets 30 from which condensate is pumped by pump 3 to a drain when the level reaches an upper limit as detected by sensor 12. The presence of two inlets 29 and outlets 30 allows the tank to be installed in several different housing configurations. A vent 31 is provided in the lid.

Claims

1. An evaporator unit for an air conditioning system, the unit being characterized in that it comprises a housing; an evaporator coil; a defined airflow path through the housing from an air inlet to an air outlet and passing over the evaporator coil; a reservoir for collecting condensate from the air passing over the evaporator coil; a sensor in the reservoir for detecting the liquid level in the reservoir; a pump for pumping condensate from the housing; at least one UV light-emitting diode (LED) mounted in the housing and arranged to radiate light onto the evaporator coil and / or the sensor; an LED driver for supplying electrical power to the LEDs; and an individual electrical power connection that can be connected to a main power source for supplying main power to the pump; wherein the LED driver is connected to the electrical power connection that supplies power to the pump.

2. The evaporator unit for an air conditioning system according to claim 1, further characterized in that at least one LED and the LED driver are removably attached within the housing and the electrical connection of the LED driver to the electrical power connection supplying power to the pump is in the form of a removable plug that connects to a connector associated with the electrical power connection supplying power to the pump.

3. The evaporator unit for an air conditioning system according to claim 1 or claim 2, further characterized in that the LED emits light with a wavelength of 100 to 280nm.

4. The evaporator unit for an air conditioning system according to any of the preceding claims, further characterized in that the LED emits light with a wavelength of 200 to 280nm.

5. The evaporator unit for an air conditioning system according to any of the preceding claims, further characterized in that the LEDs are arranged to radiate light onto the evaporator coil and are provided on an adhesive strip.

6. An evaporator unit for an air conditioning system, the unit being characterized in that it comprises a housing; an evaporator coil; an airflow path defined through the housing from an air inlet to an air outlet and passing over the evaporator coil; a reservoir for collecting condensate from the air passing over the evaporator coil; a sensor in the reservoir for detecting the liquid level in the reservoir; a pump for pumping condensate from the housing; and at least one UV LED positioned to irradiate over the sensor.

7. The evaporator unit according to claim 6, further characterized in that it additionally comprises a sensor module in which the sensor 5 and the UV LED are mounted, so that, in use, the light from the UV LED falls on the sensor.

8. The evaporator unit according to claim 7, further characterized in that the sensor module is mounted on a tank lid.

9. The evaporator unit according to claim 7 or claim 8, further characterized in that the sensor module has a power cable 10 with a plug at the end furthest from the module.

10. An air conditioning system characterized in that it comprises an evaporator unit of any of the preceding claims.

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