WO2021171254A1

WO2021171254A1 - Fan coil unit

Info

Publication number: WO2021171254A1
Application number: PCT/IB2021/051630
Authority: WO
Inventors: Giordano Valerio RIELLO; Marco REANI; Mauro TROMBINI; Giuliana GENNARO
Original assignee: Aermec S.P.A.
Priority date: 2020-02-28
Filing date: 2021-02-26
Publication date: 2021-09-02
Also published as: IT202000004216A1

Abstract

Fan coil unit (1) comprising: a rigid and substantially parallelepiped-shaped, box-like casing (2), which is structured to be firmly fixed to a wall (P), and is provided with a large pass-through duct (5) adapted to be crossed by the external air; an air-liquid heat exchanger (8) which is placed inside the pass-through duct (5) so as to be skimmed/ crossed by the air that flows along the pass-through duct (5) and is connected to an external hydraulic circuit so as to be additionally crossed by a hot or cold heat-transfer liquid; a ventilation device (9) adapted to circulate the external air through said pass-through duct (5); and a condensate-collection tray (18) that is arranged underneath the heat exchanger (8), and is adapted to collect the drops of condensed water that fall from the heat exchanger (8); and a sanitizing device (21) which is located inside the box-like casing (2), and is adapted to spray/nebulise, on command, a given amount of sanitizing liquid inside said pass-through duct (5).

Description

FAN COIL UNIT

CROSS-REFERENCE TO RELATED APPLICATIONS

This patent application claims priority from Italian patent application no. 102020000004216 filed on 28/02/2020, the entire disclosure of which is incorporated herein by reference.

TECHNICAL FIELD

The present invention relates to a fan coil unit. More in detail, the present invention relates to a wall- mounted fan coil unit.

BACKGROUND ART

As is known, wall-mounted fan coil units are substantially parallelepiped-shaped appliances, which are placed in vertical position inside the room to be air- conditioned, usually close to the floor and flush to one of the walls of the room, and are adapted to heat or cool the air inside the room.

More in detail, the fan coil units currently on the market include: a rigid and substantially parallelepiped shaped, outer box-like casing, which is structured to be firmly fixed to the wall in vertical position, more or less about ten centimetres from the floor, and is internally provided with a large pass-through duct usually with a rectangular cross-section, which extends vertically from one side of the box-like casing to the other, and is closed at the top by a protective grid; an air-liquid heat exchanger which is placed inside the duct so as to be skimmed/crossed by the air that flows along the duct, and is connected to an external hydraulic circuit so as to be continuously crossed also by a flow of hot or cold water; and an electrically- operated fan, which is placed inside the vertical pass through duct, spaced beneath the heat exchanger, and is adapted to produce an ascending airflow that travels along the entire length of the vertical pass-through duct and exits from the fan coil unit through the upper outlet mouth, crossing/skimming the heat exchanger.

Clearly, while crossing/skimming the heat exchanger, the airflow produced by the fan absorbs or releases heat to the hot/cold water that circulates in the external hydraulic circuit.

Immediately beneath the heat exchanger there is also placed a condensate-collection tray, which is adapted to collect the drops of condensed water that, in use, fall from the heat exchanger when it is crossed by cold water.

Unfortunately, experimental tests have shown that, if the fan coil unit remains inactive for medium-long periods after the heat exchanger has been crossed by cold water, in the area surrounding the heat exchanger it is created a particularly humid microclimate that promotes the uncontrolled proliferation of moulds, fungi and bacteria, with all the problems (for example bad smell) that this entails.

To overcome this drawback, the main manufacturers of fan coil units recommend to manually clean the inside of the fan coil unit at regular intervals.

Unfortunately, in most fan coil units currently on the market, the rear part of the heat exchanger can be easily reached only by removing the component from its seat. A relatively laborious operation which is clearly within the reach only of a specialised technician, with all the problems that this entails.

The end user, in fact, is generally reluctant to call the specialised technician on a regular basis in order to contain the operating costs of the fan coil unit.

DISCLOSURE OF INVENTION

Aim of the present invention is to simplify the periodic maintenance of fan coil units, while also reducing their operating costs. In accordance with the above aims, according to the present invention there is provided a fan coil unit as defined in Claim 1 and preferably, though not necessarily, in any one of the claims depending on it.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will now be described with reference to the attached drawings, which illustrate a non- limiting embodiment thereof, in which:

- Figure 1 is a perspective view of a wall-mounted fan coil unit realized according to the teachings of the present invention;

- Figure 2 is a side view of the fan coil unit shown in figure 1, sectioned along the midplane and with parts removed for clarity's sake;

- Figure 3 is a partially exploded perspective view of the fan coil unit shown in Figures 1 and 2, with parts removed for clarity's sake; whereas

- Figure 4 is a perspective view of the fan coil unit shown in Figures 1, 2 and 3, without the outer shell and the heat exchanger. BEST MODE FOR CARRYING OUT THE INVENTION

With reference to Figures 1, 2, 3 and 4, number 1 denotes as a whole a wall-mounted fan coil unit, which is adapted to heat or cool the air present inside a generic room to be air-conditioned, and is particularly adapted to be arranged inside the room to be air-conditioned in a substantially vertical position, preferably flush to one of the walls of the room and preferably at a short distance from the floor.

In addition, the fan coil unit 1 is moreover particularly adapted to be firmly anchored to the wall of the room to be air-conditioned. More in detail, the fan coil unit 1 is provided with a rigid and preferably substantially parallelepiped-shaped, outer box-like casing 2. In other words, the box-like casing 2 preferably has: a front face 2a and a rear face 2b that are opposite and substantially parallel to each other, which are substantially perpendicular to the midplane M of the fan coil unit; an upper face 2c and a lower face 2d which are opposite and preferably additionally substantially parallel to each other, and are substantially perpendicular to the midplane M of the fan coil unit and/or to the front 2a and/or rear 2b faces; and finally two side faces 2e that are opposite and preferably additionally substantially parallel to each other, and are arranged on opposite sides of the midplane M of the fan coil unit, spaced from the same midplane M.

The box-shaped casing 2, in addition, is preferably adapted to be hung/fixed on the wall P of the room to be air-conditioned in a substantially vertical position, so that the front face 2a, the rear face 2b, and the two side faces 2e are substantially vertical, and so that the upper face 2c and the lower face 2d are substantially horizontal.

Preferably, the box-like casing 2 of the fan coil unit 1 is additionally adapted to be fixed on the wall P of the room to be air-conditioned, with the rear face 2b resting/ abutting on the wall P, and preferably with the lower face 2d at about a 5-15 cm (centimetres) distance from the floor.

More in detail, the fan coil unit 1 preferably comprises: a substantially rigid and self-supporting inner framework 3, which is preferably made of metallic material, and is structured to be firmly fixed to the wall P at a given distance from the underlying floor; and a concave and substantially rigid, outer covering or shell 4, which is preferably made of metallic material, and is fixed/fitted onto the inner framework 3 so as to surround and cover the inner framework 3, forming at least the front face 2a and the two side faces 2e of the outer casing 2, and optionally also the upper face 2c and/or the lower face 2d of the outer casing 2.

In addition, the fan coil unit 1 is provided with a large pass-through duct 5 which is adapted to be crossed by the external air, and extends through the outer casing 2 preferably while remaining astride the midplane M of the fan coil unit.

More in detail, the pass-through duct 5 preferably has an approximately rectangular cross-section, and preferably extends substantially vertically from one side to the other of the box-like casing 2, so that the inlet mouth 6 of the duct is placed on the lower face 2d of the outer casing 2 and the outlet mouth 7 of the duct is placed on the upper face 2c of the outer casing 2. In other words, the inner framework 3 and the outer covering or shell 4 jointly form/delimit a substantially vertical, large pass-through duct 5 that starts at the lower face 2d of the outer casing 2 and ends at the upper face 2c.

Preferably, the inlet mouth 6 and/or the outlet mouth 7 of the pass-through duct 5 moreover is/are substantially rectangular in shape.

With reference to Figures 2 and 3, the fan coil unit 1 additionally comprises at least one air-liquid heat exchanger 8 and an electrically-operated ventilation device 9, both placed along the pass-through duct 5.

More in detail, the ventilation device 9 is preferably placed beneath the heat exchanger 8, and is adapted to circulate the external air through/along the pass-through duct 5.

In other words, the ventilation device 9 is adapted to generate an airflow f that enters into the pass-through duct 5 through the inlet mouth 6, travels through the pass-through duct 5 crossing/skimming the heat exchanger 8, and finally flows out of the fan coil unit 1 through the outlet mouth 7.

With particular reference to Figure 2, in the example shown, in particular, the ventilation device 9 is preferably placed immediately downstream of the inlet mouth 6 of the pass-through duct 5, and is preferably adapted to generate an ascending airflow f that enters the pass-through duct 5 through the inlet mouth 6 located on the lower face 2d of the outer casing 2, flows upwards crossing/skimming the heat exchanger 8, and then comes out of the fan coil unit 1 through the outlet mouth 7 placed on the upper face 2c of outer casing 2.

The heat exchanger 8, on the other hand, is adapted to be connected to an external hydraulic circuit (not shown) so as to be continuously crossed by a flow of water or other heat-transfer liquid at a given temperature, and is placed inside of the pass-through duct 5, preferably immediately upstream of the outlet mouth 7, so as to be crossed or in any case skimmed by the air that flows along the duct.

The heat exchanger 8 is therefore adapted to heat up or cool down the air that flows along the pass-through duct 5, as a function of the temperature of the water or other heat- transfer liquid crossing it.

The temperature value of the water or other heat-transfer liquid, in addition, is preferably controlled by an external cooling and/or heating unit. Preferably, the fan coil unit 1 additionally also comprises an electronic control unit 10, which is located inside the box-like casing 2, and is adapted to command the ventilation device 9 preferably on the basis of the signals coming from one or more temperature sensors (not shown) adapted to detect the temperature of the air around the fan coil I, and/or on the basis of the signals coming from one or more temperature sensors (not shown) adapted to detect the temperature of the heat exchanger 8.

In addition, with reference to Figures 3 and 4, the inner framework 3 and the outer covering or shell 4 are preferably shaped/structured so as to additionally form/delimit two lateral service compartments 11 and 12 that are arranged inside of the box-like casing 2, on opposite sides of the pass-through duct 5 and of the midplane M of the fan coil unit, so as to be both grazing/adjacent to the wall P of the room.

The service compartment 11 preferably accommodates the electronic control unit 10 and optionally also the temperature sensor (s) and/or the electrical connectors that allow connection of the fan coil unit 1, or rather of the ventilation device 9, to the external electric grid (not shown).

The service compartment 12, on the other hand, preferably accommodates the hydraulic connections, the shut-off valves and/or the other hydraulic fittings (not visible in the figures) allowing connection of the heat exchanger 8 to the external hydraulic circuit (not shown).

With reference to Figures 2, 3 and 4, in the example shown, in particular, the inner framework 3 preferably comprises: a rigid and preferably substantially rectangular- shaped, central plate-like panel 13 which is preferably made of metallic material, is arranged astride the midplane M of the fan coil unit substantially perpendicular to the latter, and is structured so as to be arranged grazing or resting on the wall P; and two rigid and preferably substantially rectangular-shaped, lateral plate-like panels 14, which are preferably made of metallic material, are arranged on opposite sides of the central plate-like panel 13 substantially parallel and facing each other and the midplane M of the fan coil unit, and connect to the central plate like panel 13 so as to form a substantially U-shaped rigid structure .

Preferably, the two lateral plate-like panels 14 additionally connect to the central plate-like panel 13 so as to protrude, when the inner framework 3 is fixed to the wall P, cantilevered from the wall P while remaining substantially vertical and perpendicular to the wall P.

The pass-through duct 5 is laterally delimited by the central plate-like panel 13 and by the two lateral plate- like panels 14. Furthermore, the central plate-like panel 13 contributes in forming the rear face 2b of the box-like casing 2.

Preferably, the service compartments 11 and 12 are, on the other hand, delimited laterally by a respective lateral plate-like panel 14 of the inner framework 3 and by a part of the outer covering or shell 4.

Preferably, the inner rigid framework 3 additionally comprises at least one substantially straight, transversal stiffening beam 15 preferably with a plate-like structure, which is preferably made of metallic material, and extends like a bridge between the two lateral plate-like panels 14, more or less perpendicular to the midplane M and to the two lateral plate-like panels 14, so as to connect the two lateral plate-like panels 14 rigidly to one another. With reference to Figures 2 and 3, the heat exchanger 8 is therefore arranged between the two lateral plate-like panels 14 of the inner rigid framework 3, and is preferably dimensioned and oriented so as to substantially take up the entire section of the pass-through duct 5. More in detail, the heat exchanger 8 has a plate-like structure and is preferably inclined by a few degrees with respect to the vertical, so as to have the upper horizontal edge resting on or in any case grazing the central plate like panel 13. Preferably, the heat exchanger 8 is moreover a finned- pack heat exchanger substantially rectangular in shape, and won't be further described as it is a component widely known in the field and easily available on the market.

With reference to Figures 2 and 3, also the ventilation device 9 is preferably placed between the two lateral plate- like panels 14 of the inner framework 3, spaced beneath the heat exchanger 8.

Furthermore, in the shown example, the ventilation device 9 preferably basically consists of a centrifugal fan with double impeller, and won't be further described as it is a component widely known in the sector and easily available on the market.

Obviously, in a different embodiment the ventilation device 9 could also be a tangential fan. With reference to Figures 1, 2 and 3, the outer covering or shell 4, on the other hand, is preferably shaped in the form of a substantially rectangular basin, and is placed to cover the inner framework 3 so as to form the front face 2a, the upper face 2c and the two side faces 2e of the box-like casing 2.

In the example shown, moreover, the outer covering or shell 4 preferably comprises: a substantially rectangular shaped, large flat plate 16 preferably made of plastic or metallic material, which is substantially U-bent so as to form the front face 2a and the two side faces 2e of the box like casing 2; and a substantially rectangular-shaped, large plate-like grid 17 preferably made of plastic or metallic material, which is fixed sideways to the upper edge of the flat plate 16 so as to form the upper face 2c of the box- like casing 2. With reference to Figures 2, 3 and 4, the fan coil unit 1 furthermore comprises a condensate-collection tray 18 and preferably also an air filter 19.

The condensate-collection tray 18 is placed inside the pass-through duct 5, immediately beneath the heat exchanger 8, and is adapted to collect and channel outside of the fan coil unit 1 the drops of condensed water that, in use, form on and fall by gravity from the heat exchanger 8 when the heat exchanger cools down the airflow f traveling through the pass-through duct 5. Preferably, the condensate- collection tray 18 moreover communicates with an external drain line (not shown), preferably so as to cause the drops of condensed water to flow by gravity directly into the same line. More in detail, the bottom of the condensate-collection tray 18 is preferably connected to the external drain line (not shown) by means of a small connection pipe (not visible in the figures) preferably made of plastic material, which is suitably inclined downwards so as to cause the drops of condensed water to flow by gravity directly into the external drain line.

In the example shown, in particular, the condensate- collection tray 18 is preferably arranged in a substantially horizontal position, immediately above the ventilation device 9, and is preferably dimensioned so as to take up the entire section of the pass-through duct 5.

In addition, the ventilation device 9, or rather the centrifugal fan with double impeller, is preferably structured so that its delivery mouth juts out upwards from the bottom of the condensate-collection tray 18.

With reference to Figures 2 and 4, the air filter 19, on the other hand, is placed along the pass-through duct 5, preferably upstream of the ventilation device 9, and is adapted to retain the dust and other impurities suspended in the air entering in the pass-through duct 5.

More in detail, the air filter 19 is preferably placed at the inlet mouth 6 of the pass-through duct 5, and is preferably dimensioned so as to substantially close the entire section of the inlet mouth 6 of the pass-through duct 5, so as to be crossed substantially by the whole airflow f which travels through the pass-through duct 5.

In other words, the air filter 19 contributes in forming the lower face 2d of the box-like casing 2.

Preferably, the air filter 19 is additionally fixed to the box-like casing 2, or rather to the inner rigid framework 3, in a manually removable manner.

In the example shown, in particular, the air filter 19 preferably has a plate-like structure and is preferably inserted in a manually removable manner in a support frame 20, which in turn is stably fixed on the lower part of the inner framework 3.

In addition, the electronic control unit 10 is preferably programmed/configured so as to interrupt/prevent operation of the ventilation device 9 when the fan coil unit 1 exceeds a given limit value of the hours of operation without maintenance of the air filter 19.

In other words, the electronic control unit 10 is preferably programmed/configured so as to count the hours of operation of the fan coil unit 1 starting from the last maintenance of the air filter 19, and to deactivate the ventilation device 9 when the hours of operation of the fan coil unit 1 reach a given limit value. Limit value upon reaching of which it is strongly recommended to carry out a new maintenance of the air filter 19. In addition or as an alternative, the electronic control unit 10 is moreover programmed/configured so as to activate, when the fan coil unit 1 exceeds the aforementioned given limit value of the hours of operation without maintenance of the air filter, an acoustic and/or light signaler which is preferably placed on the control panel of the fan coil unit (not visible in the figures).

In the example shown, in particular, the electronic control unit 10 is preferably programmed/configured so as to activate the acoustic and/or light signaler and block the ventilation device 9 when the fan coil unit 1 exceeds, for example, 200 hours of operation without maintenance of the air filter 19.

With reference to figures 2, 3 and 4, in addition the fan coil unit 1 also comprises an electrically-operated sanitizing device 21, which is placed inside the box-like casing 2, and is adapted to selectively spray/nebulise some sanitizing liquid inside the pass-through duct 5, so as to contrast/prevent the proliferation of moulds, fungi and/or bacteria inside the pass-through duct 5, around the heat exchanger 8 and/or on the condensate-collection tray 18.

More in detail, the sanitizing device 21 is preferably adapted to spray/nebulise, on command and each time, a given amount of sanitizing liquid inside the pass-through duct 5, towards/against the heat exchanger 8. In other words, the sanitizing device 21 is preferably adapted to wet the body of the heat exchanger 8 with the sanitizing liquid. Preferably, the amount of sanitizing liquid sprayed each time is moreover lower than 10 ml (millilitres) . The sanitizing liquid is a chemical product easily available on the market (it generally contains sodium hypochlorite in a percentage lower than 2%), so it won't be further described.

More in detail, the sanitizing device 21 is preferably structured so as it is able to spray/nebulise the sanitizing liquid on the rear face of the heat exchanger 8, i.e. on the face of heat exchanger 8 turned towards the central plate like panel 13 and/or the wall P.

In addition, the electronic control unit 10 is preferably programmed/configured so as to activate the sanitizing device 21 at predetermined time deadlines and/or when the fan coil unit 1 has exceeded a given limit value of the hours of operation without performing a sanitisation of the heat exchanger. In other words, the electronic control unit 10 is preferably programmed/configured so as to count the hours of operation of the fan coil unit 1 starting from the last sanitization of the heat exchanger 8, and to activate the sanitizing device 21 when the hours of operation of the fan coil unit 1 reach a given limit value.

Preferably, the electronic control unit 10 is moreover programmed/configured so as to deactivate the ventilation device 9 at same time of the activation of the sanitizing device 21, or rather immediately before the activation of the sanitizing device 21, and optionally for a given time.

In addition or as an alternative, the electronic control unit 10 is preferably programmed/configured so as to activate the sanitizing device 21, at predetermined and more or less regular intervals, regardless of the hours of operation of the fan coil unit 1. Preferably, the electronic control unit 10 is moreover programmed/configured so as to activate the sanitizing device 21 when the fan coil unit 1 has operated continuously in the summer or cooling configuration, i.e. when the heat exchanger 8 is crossed by a flow of water or other heat- transfer liquid with a temperature lower than the ambient one.

In other words, in the summer configuration the fan coil unit 1 cools down the air that circulates inside the pass through duct 5.

In the example shown, in particular, the electronic control unit 10 is preferably programmed/configured so as to activate the sanitizing device 21 when the fan coil unit 1 exceeds, for example, the 100 hours of operation without performing sanitization of the heat exchanger 8.

In addition, the electronic control unit 10 is preferably programmed/configured so as to activate the sanitizing device 21 on a monthly basis, for example, preferably only when the fan coil unit 1 has operated continuously in the summer or cooling configuration.

With reference to Figures 2, 3 and 4, the sanitizing device 21 preferably comprises: a storage tank 22 for the sanitizing liquid, which is located inside the box-like casing 2 and contains/is adapted to contain a large amount of sanitizing liquid to be sprayed in the pass-through duct 5; one or more nozzles 23 which are placed inside the pass through duct 5, and are adapted to spray/nebulise the sanitizing liquid coming from the tank 22 inside the pass through duct 5, preferably towards the heat exchanger 8; and an electrically-operated feeding pump 24 which is placed inside the box-like casing 2 and is adapted to pump, on command, the liquid contained into the tank 22, from the tank 22 towards the nozzle or nozzles 23.

More in detail, the tank 22 is preferably located inside the service compartment 12, and preferably has a capacity ranging between 0,1 and 2 litres.

The feeding pump 24 is preferably also located inside the service compartment 12, optionally immediately beneath the tank 22. The nozzle or nozzles 23, on the other hand, are preferably arranged/oriented so as to be able to spray/ nebulise the sanitizing liquid coming from the tank 22 directly against the rear face of the heat exchanger 8.

Preferably, the sanitizing device 21 moreover includes also an auxiliary control module (not visible in the figures) preferably separate and distinct from the electronic control unit 10, that commands the feeding pump 24 and is programmed /configured to activate, on command, the feeding pump 24 for a given time interval preferably lower than 120 seconds.

The electronic control unit 10 of fan coil unit 1, in turn, is preferably adapted to command the control module of the sanitizing device 21.

Clearly in a different embodiment, the auxiliary control module could be incorporated in the electronic control unit 10 of fan coil unit 1.

In other words, the electronic control unit 10 could directly command the feeding pump 24, and be programmed/ configured so as to activate the feeding pump 24 for a predetermined time interval when the sanitation of the heat exchanger 8 is required.

In addition, the electronic control unit 10 is preferably also programmed/configured so as to signal, by means of acoustic and/or visual signals, when the level of the sanitizing liquid inside the tank 22 lowers below a given limit value.

More in detail, the sanitizing device 21 preferably additionally includes a level sensor (not visible in the figures) which is adapted to detect the level of the liquid present inside the tank 22. The electronic control unit 10, in turn, is preferably connected to said level sensor, and is programmed/configured so as to activate a suitable acoustic and/or light signaler preferably placed on the control panel of the fan coil unit (not visible in the figures), as a function on the signals coming from the same level sensor. With reference to Figures 2, 3 and 4, in the example shown, finally, the nozzle or nozzles 23 are preferably placed along an oblong-shaped, common feeding manifold 25 that extends inside the pass-through duct 5 spaced above the condensate-collection tray 18, and the feeding pump 24 is adapted to pump the sanitizing liquid at inlet of the feeding manifold 25.

Preferably, the feeding manifold 25 is moreover substantially rectilinear and optionally extends inside the pass-through duct 5 transversely to the airflow f that circulates in the duct.

In the example shown in particular, the feeding manifold 25 preferably extends inside the pass-through duct 5 while remaining substantially perpendicular to the midplane M.

In the example shown, moreover, the feeding manifold 25 is preferably made of metallic material, and preferably extends like a bridge between the two lateral plate-like panels 14 of inner framework 3, preferably while remaining substantially skimmed over the central plate-like panel 13.

Furthermore, the nozzles 23 are preferably distributed in a substantially regular manner along the entire length of the feeding manifold 25.

The tank 22, on the other hand, is preferably made of plastic material, and is preferably provided with a removable cap 26. Finally, the feeding pump 24 is preferably a diaphragm pump, and is preferably placed underneath the tank 22.

Preferably, the fan coil unit 1 additionally also comprises an electrically-operated humidifier device 31, which is located inside the box-like body 2, and is adapted to selectively spray/nebulise some water inside the pass through duct 5, so as to increase the humidity content of the airflow f that flows out of the fan coil unit 1.

More in detail, the humidifier device 31 is preferably adapted to spray/nebulise inside the pass-through duct 5, on command and each time, a given amount of water preferably lower than 2 ml (millilitres).

Preferably, the humidifier device 31 is additionally structured so as to spray/nebulise the water inside the pass- through duct 5, above the condensate-collection tray 18.

Optionally, the sprayed/nebulised water inside the pass through duct 5 may additionally contain perfumed essences of a known type.

Preferably, the electronic control unit 10 is moreover programmed/configured so as to activate the humidifier device 31 when the humidity content of the air that flows out of the fan coil unit 1 lowers below a given limit value.

More in detail, the electronic control unit 10 is preferably connected to at least one humidity sensor which is adapted to detect the humidity content of the air entering and/or surrounding the fan coil unit 1, and is adapted to activate the humidifier device 31 depending on the signals coming from said humidity sensor.

In addition or as an alternative, the electronic control unit 10 is preferably programmed/configured so as to activate the humidifier device 31 at predetermined time deadlines, when the fan coil unit 1 operates in the winter or heating configuration and supplies hot air at the outlet.

In other words, in the winter configuration the heat exchanger 8 is crossed by a flow of water or other heat- transfer liquid with a temperature higher than the ambient one, and the fan coil unit 1 thus heats up the air that circulates inside the pass-through duct 5.

More in detail, the electronic control unit 10 is preferably programmed/configured so as to activate the humidifier device 31 at regular intervals, when the fan coil unit 1 operates continuously in the winter or heating configuration .

In the example shown, in particular, the electronic control unit 10 is preferably programmed/configured so as to activate the humidifier device 31 when the relative humidity content of the air leaving the fan coil unit 1 drops below 30%, and/or so as to activate the humidifier device 31 every 10-15 minutes when the fan coil unit 1 operates continuously in the winter or heating configuration. With reference to Figures 2, 3 and 4, the humidifier device 31 preferably comprises: a water storage tank 32, preferably with a capacity greater than that of tank 22 of sanitizing device 21, which is adapted to contain a large amount of water to be sprayed on the heat exchanger 8, possibly added with perfumed essences, and is located inside the box-like casing 2; one or more nozzles that are adapted to nebulise the water coming from tank 32 inside the pass through duct 5; and a second electrically-operated feeding pump 34 which is placed inside the box-like casing 2, and is adapted to pump, on command, the liquid contained in the tank 32, from the tank 32 towards the aforementioned nozzle or nozzles.

More in detail, the tank 32 is preferably located inside the service compartment 12, preferably beside tank 22, and preferably has a capacity ranging between 0,5 and 4 litres. Also the feeding pump 34 is preferably located inside the service compartment 12, optionally immediately beneath the tank 32. Preferably, the humidifier device 31 moreover includes also a second auxiliary control module (not visible in the figures) preferably separate and distinct from the electronic control unit 10 and/or from the auxiliary control module of sanitizing device 21, which commands the feeding pump 34 and is programmed/configured so as to activate, on command, the feeding pump 34 for a given time interval preferably lower than 60 seconds.

The electronic control unit 10 of fan coil unit 1, in turn, is preferably adapted to command the control module of humidifier device 31.

Clearly in a different embodiment, also the control module of humidifier device 31 could be incorporated in the electronic control unit 10 of fan coil unit 1.

In other words, the electronic control unit 10 could directly command the feeding pump 34, and be programmed/ configured so as to activate the feeding pump 34 for a given time interval when it is necessary to increase the humidity content of the air that flows out of the fan coil unit 1.

In addition, the electronic control unit 10 is preferably also programmed/configured so as to activate, when the water level inside the tank 32 lowers below a predetermined limit, a suitable acoustic and/or light signaler which is preferably placed on the control panel of the fan coil unit (not visible in the figures). Furthermore, in the example shown, the humidifier device

31 is preferably structured so as to be able to spray/ nebulise, on command, the water directly on the body of the heat exchanger 8.

In other words, similarly to the sanitizing device 21, the humidifier device 31 is preferably structured so as to be able to nebulise the water directly on the rear face of the heat exchanger 8, i.e. on the face of the heat exchanger 8 turned towards the central plate-like panel 13 and/or the wall P. Preferably, the humidifier device 31 is moreover structured so as to nebulise the water inside the pass through duct 5, or rather directly on the body of the heat exchanger 8, using the nozzle or nozzles 23 of the sanitizing device 21. More in detail, in the example shown, the delivery of the feeding pump 34 of humidifier device 31 is preferably connected directly to the transversal manifold 25, so as to allow the feeding pump 34 to pump the water of tank 32 at inlet of the transversal manifold 25. Similarly to the tank 22, also the tank 32 is preferably made of plastic material, and is preferably provided with a removable cap 36.

Finally, similarly to feeding pump 24, also feeding pump 34 is preferably a diaphragm pump, and is preferably located underneath the tank 32.

Operation of the fan coil unit 1 is easily inferable from what written above.

The fan coil unit 1 is capable of automatically spraying the sanitizing liquid on the body of the heat exchanger 8 and/or on the condensate-collection tray 18, so as to contrast/prevent the proliferation of moulds, fungi and/or bacteria inside the pass-through duct 5.

In addition, fan coil unit 1 is capable of automatically spraying/nebulising water inside the pass-through duct 5, so as to increase, if necessary, the humidity content of the hot air that flows out of the fan coil unit 1.

The advantages connected to the presence of the sanitizing device 21 and optionally also to that of the humidifier device 31 are noteworthy. Firstly, the fan coil unit 1 has operating costs significantly lower than those of the fan coil units currently on the market, because it is capable of sanitizing the heat exchanger area in a completely automatic manner.

The end user has to solely fill up the tank 22 every now and then with the sanitizing liquid.

Moreover, the presence of sanitizing device 21 makes it possible to nebulise, without particular restrictions, some water inside the pass-through duct 5 to increase the relative humidity content of the air, with the certainty that this water will not cause uncontrolled proliferation of moulds, fungi and/or bacteria inside the pass-through duct 5.

The electronic control unit 10, in fact, can periodically activate the sanitizing device 21 even when the fan coil unit 1 operates continuously in the winter or heating configuration, so as to avoid that the water nebulised inside the duct 5 from the humidifier device 31 can lead to an uncontrolled proliferation of moulds, fungi and/or bacteria inside the pass-through duct 5.

It is finally clear that modifications and variations may be made to the fan coil unit 1 described above without however departing from the scope of the present invention.

For example, the sanitizing device 21 and the humidifier device 31 can also share the feeding pump that pumps the sanitizing liquid/water to the nozzles 23. In other words, the feeding pump 24 of sanitizing device

21 can also be connected to the tank 32 of the humidifier device 31.

In this case, the sanitizing device 21 is additionally provided with an electro-controlled valve assembly that is interposed between the feeding pump 24 and tanks 22 and 32, and is adapted to put the suction mouth of feeding pump 24 in fluid communication selectively and alternatively with the tank 22 or with the tank 32.

Clearly, the electronic control unit 10 is programmed/ configured so as to command the feeding pump 24 and the valve assembly, so as to be able to temporarily supply to the nozzles 23, or rather to the oblong transversal manifold 25, alternatively water or sanitizing liquid.

Claims

1. A fan coil unit (1) comprising: a rigid and substantially parallelepiped-shaped, box-like casing (2) which is structured to be firmly fixed to a wall (P), and is provided with a large pass-through duct (5) adapted to be crossed by the external air; an air-liquid heat exchanger (8) which is placed inside the pass-through duct (5) so as to be skimmed/crossed by the air that flows along the pass through duct (5), and is connected to an external hydraulic circuit so as to be additionally crossed by a hot or cold heat-transfer liquid; electrically-operated ventilation means (9) adapted to circulate the external air through said pass-through duct (5); and a condensate-collection tray (18) that is arranged underneath the heat exchanger (8), and is adapted to collect the drops of condensed water that fall from the heat exchanger (8); the fan coil unit (1) being characterised by additionally comprising an electrically-operated sanitizing device (21) which is located inside the box-like casing (2), and is adapted to selectively spray/nebulise a sanitizing liquid inside the pass-through duct (5).

2. Fan coil unit according to Claim 1, wherein the sanitizing device (21) is adapted to spray/nebulise the sanitizing liquid onto the body of the heat exchanger (8).

3. Fan coil unit according to Claim 1 or 2, wherein the sanitizing device (21) comprises: a first tank (22) which is adapted to contain the sanitizing liquid to be sprayed in the pass-through duct (5); one or more nozzles (23) that are adapted to spray/nebulise the sanitizing liquid coming from said first tank (22) inside the pass-through duct (5), preferably towards the heat exchanger (8); and a first feeding pump (24) which is adapted to pump, on command, the liquid contained into the first tank (22), from said first tank (22) towards said nozzle or nozzles (23).

4. Fan coil unit according to Claim 3, wherein the sanitizing device (21) is provided with a transversal oblong manifold (25) that extends inside the pass-through duct (5) spaced above the condensate-collection tray (18), and the nozzles (23) are distributed along said transversal oblong manifold (25); the first feeding pump (24) being adapted to pump the sanitizing liquid into said transversal oblong manifold (25).

5. Fan coil unit according to Claim 3 or 4, wherein the sanitizing device (21) additionally comprises an auxiliary control module that commands said first feeding pump (24) and is programmed/configured so as to activate, on command, the first feeding pump (24) for a predetermined time interval.

6. Fan coil unit according to any one of the preceding claims, characterised by additionally comprising an electronic control unit (10) which is housed inside the box like casing (2) and is programmed/configured so as to activate said sanitizing device (21) at predetermined time deadlines, and/or when the fan coil unit (1) has exceeded a given operation time limit without performing sanitisation.

7. Fan coil unit according to Claim 6, wherein said electronic control unit (10) additionally command said ventilation means (9), and is preferably programmed/ configured so as to deactivate the ventilation means (9) at same time of the activation of the sanitizing device (21).

8. Fan coil unit according to any one of the preceding claims, wherein the external box-like casing (2) comprises: a substantially rigid and self-supporting inner framework (3) which is structured to be fixed firmly to the wall (P); and an outer covering or shell (4) which is fixed/fitted onto the inner framework (3) so as to surround and cover the same inner framework (3), forming at least the front face (2a) and the two side faces (2e) of said box-like casing (2).

9. Fan coil unit according to Claim 8, wherein said inner framework (3) and said outer covering or shell (4) are shaped /structured so as to additionally form/delimit two lateral service compartments (11, 12) that are arranged inside of said box-like casing (2), on opposite sides of the pass through duct (5), so as to be both grazing/adjacent to the wall (P) of the room; a first service compartment (11) being adapted to accommodate the electronic control unit (10) and optionally also one or more temperature sensors and/or electrical connectors that allow connection of the fan coil unit (1) to the external electric grid; the second service compartment (12) being adapted to accommodate the hydraulic connections, the shut-off valves and/or the other hydraulic fittings allowing connection of the heat exchanger (8) to the external hydraulic circuit.

10. Fan coil unit according to Claim 9, wherein the second service compartment (12) additionally accommodates said first tank (22) and/or said first feeding pump (24) of the sanitizing device (21).

11. Fan coil unit according to any one of the preceding claims, characterised by additionally comprising an electrically-operated humidifier device (31) which is placed inside the box-like body (2) and is adapted to spray/ nebulise, on command, a given amount of water inside said pass-through duct (5), so as to increase the humidity content of the air that flows out of the fan coil unit (1).

12. Fan coil unit according to Claim 11, wherein said electronic control unit (10) is programmed/configured so as to activate the humidifier device (31) at predetermined time deadlines, when the fan coil unit (1) heats up the air that circulates inside the pass-through duct (5).

13. Fan coil unit according to claim 11 or 12, wherein said electronic control unit (10) is programmed/configured so as to activate the humidifier device (31) when the humidity content of the air that flows out of the fan coil unit (1) drops below a given limit value.

14. Fan coil unit according to claim 11, 12 or 13, wherein the humidifier device (31) comprises: a second tank (32) which is adapted to contain the water to be nebulised inside the pass-through duct (5); one or more nozzles (23) that are adapted to spray/nebulise the sanitizing liquid coming from said second tank (32) inside of the pass-through duct (5); and a second feeding pump (24, 34) which is adapted to pump, on command, the liquid contained inside the second tank (32), from said second tank (32) towards said nozzle or nozzles (23).

15. Fan coil unit according to Claim 14, wherein the humidifier device (31) nebulises the water inside the pass through duct (5) by means of the nozzle or nozzles (23) of the sanitizing device (21).