GB2433586A

GB2433586A - An air conditioning system

Info

Publication number: GB2433586A
Application number: GB0602303A
Authority: GB
Inventors: Peter Quentin Lowther
Original assignee: Individual
Current assignee: Individual
Priority date: 2005-12-22
Filing date: 2006-02-06
Publication date: 2007-06-27
Anticipated expiration: 2026-02-06
Also published as: GB2433586B; GB0602303D0; GB0526155D0

Abstract

An air conditioning system comprises an inlet chamber 2 having a plurality of outlets, each being provided with a connection 22 that connects to a respective duct 5, 7, 9 and at least one pump 17 operative to pump air from the inlet chamber 2 through at least one temperature control coil 19 to control the temperature of the air to the ducts 5, 7, 9, and each connection 22 being sealed from the other connection(s) 22 so that air is only pumped through the duct 5, 7, 9 connected to that connection 22. Connection 22 may be connected to a plenum chamber 3 divided into sealed sub-chambers 11 by plates 13 or individual plenum chambers (figs 4 - 6). The pump(s) 17 may be independently controlled fans, each driven by an impellor mounted on a rotor (21, fig 2) of a speed adjusted/controlled brushless motor (20) that is controlled by a remote controller (35, fig 3) that an operator can vary. Controller 35 may receive signals from a temperature sensor (37), sensors for air pressure and flow rate in particular parts of a building, or fluid control valves (39) to control the flow of fluid though the coil(s) 19, which may be mounted downstream of the fans 17. Motor (20) may be provided with a Hall-effect sensor to determine the rotational position of the rotor (21).

Description

A FAN COIL AIR CONDITIONING SYSTEM AND INLET

THEREFOR

The present invention relates to a fan coil air conditioning system and to an inlet for such a system.

Fan coil air conditioning systems are well known and typically comprise a chamber comprising a coil through which temperature controlled fluid flows. Air is drawn into the chamber and over the coil using a fan. The temperature and or volume of the air is thus controlled by the temperature of the fluid flowing through the coil. The air is then pumped from the chamber to the appropriate part of a building through air delivery ducts connected to the chamber.

The chamber is typically provided with a number of fans powered by AC motors that are all controlled by a single transformer in combination with switches. The speed of the fans can therefore not be individually controlled and thus the fans all run at the same speed. Additionally this speed can typically only be adjusted in steps using the output voltage of the transformer.

The ducts through which air is pumped are typically of differing lengths depending on where in the building the ducts terminate. Thus the resistance to air flow varies from duct to duct. This results in the requirement to balance the air flow through each duct such that one duct does not receive a disproportionately high volume of air in comparison to the other ducts. Typically this balancing is achieved by providing air volume control dampers at a point within each duct. Such dampers, which can be butterfly type valves extending across the duct, can be adjusted such that the air flow through each duct is set to a desired level.

However, the dampers effectively restrict the diameter of some or all of the ducts and this increases the load on, and thus the speed of, the fan motor(s) which, in turn, increases the amount of power consumed. This increase in motor speed also increases the heat generated by the fan motors and this heat generation can adversely affect control of the temperature of the pumped air, particularly when it is desired to cool the air. The dampers also generate noise as the air passes over the damper blades, which are typically metal.

Furthermore, the balancing process can be relatively time consuming firstly because the dampers are typically awkward to access, and secondly because the balancing process is reiterative. This is because, when a damper has been adjusted to provide the desired air flow in one duct, this also affects the resistance to air flow in the other ducts. This leads to the dampers in those other ducts also then needing adjustment.

Thus the balancing process needs to be repeated to obtain air flows in each duct that are substantially equal and that are as close as possible to the desired level. This process is often made more difficult because the fan motor speed control, and the dampers themselves, are typically located in different areas of the building.

The dampers therefore add significantly to the capital cost, and to the time cost, of installing an air conditioning system.

According to a first aspect of the invention there is provided a fan coil air conditioning system inlet, the inlet comprising an inlet chamber which comprises a plurality of outlets, each outlet being provided with a respective connection to connect the outlet, in use, to a respective air delivery duct in the air conditioning system, each outlet being adapted to be connected, in use, to pump means operative to pump air from the inlet chamber to the air delivery ducts via the connections, the air inlet chamber being adapted to be provided, in use, with at least one temperature control coil to control the temperature of the air pumped through the connections, each connection being sealed from the other connection(s), such that air pumped through a connection only enters the air delivery duct connected to that connection.

Preferably a single temperature control coil is provided to control the temperature of air pumped through the connections.

However, in an alternative embodiment, a respective temperature control coil is provided for each connection. In such an embodiment, each temperature control coil is therefore operative to control the temperature of the air pumped through the respective connection and into the associated air conditioning duct independently of the air pumped through the other connection(s).

Preferably the or each temperature control coil is mounted on the inlet chamber.

In one embodiment the inlet chamber is provided with an outlet plenum chamber, the connections connecting the air conditioning ducts, in use, to the outlet plenum chamber.

Preferably the plenum chamber comprises a plurality of sub chambers, each sub chamber comprising, in use, a respective connection between an outlet of the inlet chamber and a respective air conditioning duct, each sub chamber being sealed from the other sub chamber(s).

Each connection may comprise a tubular connector.

In another embodiment each connection comprises an individual plenum chamber each of which is in communication with a respective outlet of the inlet chamber Preferably each connection is provided with a spigot type connector adapted to be sealingly received in the inlet end of a respective air conditioning duct. Preferably the fan coil inlet chamber comprises pump means operative to pump air through the outlets and through the connections.

Preferably the pump means comprises a fan.

Preferably the fan coil inlet chamber comprises a plurality of fans, each fan being in communication with a respective connection.

The volume of air pumped through each connector can thus be independent of the volume of air pumped through each other connector.

The volume and flow rate of air pumped through one connector and into one air conditioning duct can therefore be controlled independently of the air pumped through the other connector(s) and into the other air conditioning duct(s).

Preferably each fan comprises a motor which drives, in use, an impellor, the impellor being connected directly, that is without intermediary, to the rotor of the motor.

Preferably the motor is electronically commutated, that is, the commutation of the coils of the motor is controlled by electronic control means.

Preferably the electronic control means is mounted on the fan.

The rotor of the motor is provided with a plurality of permanent magnets which are driven by a stator that comprises a plurality of electrically conducting windings that are selectively powered in use by the electronic control means.

The electronic control means may comprise a Hall-effect sensor that determines the rotational position of the rotor relative to the stator based on a signal generated by a change in potential difference as the rotor magnets rotate about the stator, the commutation of the motor being dependent on the output of the Hall-effect sensor.

The electronic control means preferably comprises an AC to DC converter that converts a mains input (typically approximately 230V) to a DC output voltage.

A 10 volt DC output from the electronic control means is preferably input to a user operated controller which sends a converted DC signal voltage back to the electronic control means, the electronic control means being operative such that the speed of rotation of the rotor is dependent upon the DC signal voltage.

The DC signal voltage is preferably adjustable using the controller and is most preferably adjustable via a user controlled input means such as a rotary adjuster provided on the controller for example.

Preferably the speed of each fan can be adjusted/controlled independently of the speed of the other fans.

The user operated controller may be adapted to receive input signals from other input means such as sensors comprising, for example, pressure, temperature, or fluid flow rate sensors remote from the controller.

According to a second aspect of the invention there is provided a fan coil air conditioning system comprising an inlet provided with an inlet chamber the inlet chamber comprising a plurality of outlets each provided with a respective connection each of which connects one outlet to a respective air delivery duct of the air conditioning system, pump means being provided to pump air through the connections, at least one temperature control coil being provided to control the temperature of air pumped through the connections, each connection being sealed from the other connection(s), such that air pumped through a connection only enters the air delivery duct connected to that connection.

Preferably a single temperature control coil is provided to control the temperature of air pumped through the connection(s).

However, in an alternative embodiment, a respective temperature control coil is provided for each connection. In such an embodiment, each temperature control coil is therefore operative to control the temperature of the air pumped through the respective connection independently of the air in the other connection (s).

In one embodiment, the inlet chamber is provided with an outlet plenum chamber, the connections connecting the air conditioning ducts to the outlet plenum chamber.

Each connection may comprise a tubular connector.

In another embodiment each connection comprises an individual plenum chamber each of which is in communication with a respective outlet of the inlet chamber.

Preferably each connection is provided with a spigot connector adapted to be sealingly received in the inlet end of a respective air conditioning duct. Preferably the means to pump air comprises a fan.

Preferably the system comprises a plurality of fans, each fan being in communication with a respective connection.

Preferably each fan comprises a motor which drives, in use, an impellor.

Preferably the impellor is connected directly, that is without intermediary, to the rotor of the motor.

Preferably the motor is electronically commutated, that is, wherein the commutation of the coils of the motor is controlled by electronic control means.

Other aspects of the present invention may include any combination of the features or limitations referred to herein.

The present invention may be carried into practice in various ways, but embodiments will now be described by way of example only with reference to the accompanying drawings in which: Figure 1 is a schematic view of a fan coil air conditioning system and inlet in accordance with the present invention; Figure 2 is a part cut-away perspective view of a fan motor comprising part of the system of Figure 1; Figure 3 is a schematic view of part of the system of Figures 1 and 2; Figure 4 is a plan view of an alternative embodiment of the inlet of the air conditioning system of Figures 1 to 3; Figure 5 is a plan view of a further alternative embodiment of the inlet of the air conditioning system of Figures 1 to 3; and Figure 6 is a plan view of another alternative embodiment of the inlet of the air conditioning system of Figures 1 to 3.

Referring initially to Figure 1, a fan coil air conditioning system 1 comprises an inlet in the form of an inlet chamber 2 provided, in this embodiment, with a plenum chamber 3 and three air conditioning delivery ducts 5, 7 and 9. It will be appreciated that the system 1 is exemplary and that any desired size of plenum chamber 3 and any number of air delivery ducts, could be provided.

The inlet chamber 2 is substantially cuboid and comprises, in this example, three outlet apertures (not shown) formed in the back wall of the inlet chamber 2.

The plenum chamber 3 is formed from a cuboid of plate metal that is divided into three sub chambers 11 by dividing plates 13. The dividing plates 13 form a fluid seal between each sub chamber 11. The plenum chamber 3 can comprise separate sub chambers formed in any other suitable manner including sub chambers that are pre-moulded or pre fabricated.

Each sub chamber 11 is provided with an air inlet 15 and an air outlet 18.

The air inlet 15 of each sub chamber 11 comprises an inlet aperture formed in the front wall of the sub chamber 11 and is sealingly connected to a respective outlet aperture of the inlet chamber 2. A respective fan 17 is connected to each outlet aperture of the inlet chamber 2 such that, in use, air is pumped by the fan 17 through the apertures and into the respective sub chamber 11.

The air outlet 18 of each sub chamber 11 comprises a tubular spigot type connector 22 which is sealingly received within one end of a respective air delivery duct 5 to 9.

The sub chambers 11 thus comprise connections between the air inlet chamber 2, and the air delivery ducts 5 to 9, each connection being sealed from the other connections so that air pumped through one connection does not subsequently mix with air pumped through the other connections.

In the illustrated embodiment, three temperature control coils 19 are mounted on the inlet chamber 2, each coil 19 being mounted adjacent the fan inlet of a respective sub chamber 11. Each coil 19 is connected to a source of temperature controlled fluid (not shown) operative to pump the temperature controlled fluid through the coil 19. The source of fluid could comprise a separate heating or cooling device located remote from the inlet chamber 2 and plenum chamber 3 and may utilise, for example, a fluid such as water or refrigerant. The fluid can pass through a heat exchanger if necessary.

Each sub chamber (connection) 11 is thus provided with its own air inlet 15 and air outlet 18 to provide air to a respective one of the air ducts 5 to 9, the air provided to each air duct 5 to 9 thus being separate to the air provided to the other ducts 5 to 9. The temperature and/or volume flow rate of air in each sub chamber 11 can therefore be controlled independently of the other sub chambers 11.

Each fan 17 comprises an electronically commutated (EC) motor 20.

Each motor 20 comprises a rotor 21 provided with permanent magnets 23, the rotor 21 and magnets 23 being rotatably mounted on a stator 25 comprising an axle 26 mounted on an axially spaced pair of bearings 27. The fan impellor (not shown) is mounted directly on the rotor 21 to rotate with, and at the same speed as, the rotor 21.

The stator 25 comprises a plurality of electrically conductive windings 29 that generate an electromagnetic field when a current is applied to the windings 29.

The motor 20 thus comprises a brushless motor wherein the commutation of the motor 20 is controlled by electronic control means comprising an electronic circuit housed in the rear housing 31 of the fan 17. In use, the electronic circuit switches the current to the different stator windings 29 at the appropriate times such that the rotor 21 is driven about the stator 25. The switching is dependent on the rotational position of the rotor 21 relative to the stator 25.

The motor 20 is provided with a Hall-effect sensor 33 operative to determine the rotational position of the rotor 21 by detecting the change in potential difference generated across the permanent magnets 23 of the rotor 21 as a result of the magnets 23 rotating within the electro magnetic

field generated by the stator windings 29.

The electronic circuit could alternatively comprise means to use the back voltage in the undriven stator windings 29 to sense the position of the rotor 21 and in that case the Hall-effect sensor 33 would not be required.

With reference to Figure 3, each EC motor 20 is connected in use to a mains AC electricity input voltage source (typically approximately 230V). That AC input voltage is converted into a DC driving voltage (typically approximately 48V) via an AC to DC power converter provided within the rear housing 31. The DC driving voltage is used to drive the motor windings 29.

The power converter also feeds a DC output voltage (typically approximately 1OV) to a remote controller 35. The operator can use the controller 35 to vary the DC output voltage to create a DC control voltage that is output from the controller 35 and back to the electronic control means to control the voltage sent to the stator windings 29.

Thus, by varying the magnitude of the DC control voltage, the operator can control the speed of the motor 20. It will be appreciated that such control has infinite adjustment within the upper and lower voltage limits available. This enables the speed of each EC motor 20 to be controlled as desired by the operator rather than in steps using stepped control voltages of a transformer (as provided with previous AC motors).

The controller 35 could be any suitable controller, including for example, a rotary potentiometer.

The speed of each EC motor 20 could alternatively be controlled by a control signal provided from another source.

The controller 35 can generate a control voltage using input signals from other devices such as, for example, a temperature sensor 37 which provides a signal indicative of the air temperature in a part of the building, or of the temperature of the air being returned from a part of the building so as to be reheated or cooled. Additional sensors may be provided to generate signals relating to, for example, air pressure and air flow rate for a particular part or parts of the building. The temperature sensor 37 can be, for example, a thermistor or thermocouple type sensor.

The controller 35 can also receive input signals from, and control the operation of, fluid control valves 39. Each valve 39 comprises an actuator to control the opening of the valve 39. Each valve 39 is operative to control the flow rate of the fluid through the or each temperature control coil 19.

In use the operator can control each individual temperature control coil 19, and each EC motor 20, such that the desired temperature and flow rate of air is provided to each duct 5 to 9 depending on the length of each duct 5 to 9 and the temperature requirements for the area of the building at the end of each duct 5 to 9. The commissioning of the system 1 is relatively straightforward and is not reiterative because the flow rate of air in one duct 5 to 9 is independent of the flow rate of air in the other duct(s) 5 to 9. Thus adjustment of the flow rate in one duct 5 to 9 does not then necessitate adjustment of the flow rate in another duct 5 to 9.

No volume control dampers are required which reduces the capital cost of installing, and the cost of commissioning, the system 1. The load on each motor 20 is reduced and thus the noise is reduced because the ducts 5 to 9 are not restricted and because the motors 20 are therefore running more slowly for a given air flow rate. This also results in a lower power consumption of the system 1.

The flow rate of air in each duct 5 to 9 is conveniently controlled by varying the DC control voltage to each EC motor 20. The controller 35 can be located in any suitable convenient position in the building.

Any number of temperature control coils 19 can be provided as required.

It is envisaged that only one upstream temperature control coil 19 may be provided, that single temperature control coil 19 controlling the temperature of air that is distributed to all of the ducts 5, 7, 9.

In an alternative embodiment, the temperature control coils 19 can be mounted downstream of the fans 17 such that, for example, a coil 19 is mounted in each sub chamber 11.

Figures 4 to 6 illustrate alternative embodiments of the inlet chamber 2 of the air conditioning system 1.

Referring to Figure 4, the air inlet chamber 2 is provided with connections comprising separate plenum chambers 50, each of which is in communication with a respective outlet aperture of the inlet chamber 2.

Each separate plenum chamber 50 is provided with a respective spigot connector 22 for sealing insertion into one end of an air delivery duct 5 to 9.

Referring to Figure 5, the air inlet chamber 2 is provided with connections comprising hollow mouldings or fabrications or devices 60 that are secured over respective outlet apertures of the inlet chamber 22.

Each moulding 60 is provided with a respective spigot connector 22 for sealing insertion, into one end of an air delivery duct 5 to 9.

Referring to Figure 6, the air inlet chamber 2 is provided with connections comprising only tubular spigot type connectors 22 each of which is sealingly inserted, in use, into one end of a respective air delivery duct 5 to 9.

It will be appreciated that the connections can comprise any suitable air tight means operative to form a sealed air flow channel between an outlet aperture of the inlet chamber 2 and one of the air delivery ducts 5 to 9.

Claims

CLAIMS

1. A fan coil air conditioning system inlet, the inlet comprising an inlet chamber which comprises a plurality of outlets, each outlet being provided with a respective connection to connect the outlet, in use, to a respective air delivery duct in the air conditioning system, each outlet being adapted to be connected, in use, to pump means operative to pump air from the inlet chamber to the air delivery ducts via the connections, the air inlet chamber being adapted to be provided, in use, with at least one temperature control coil to control the temperature of the air pumped through the connections, each connection being sealed from the other connection(s), such that air pumped through a connection only enters the air delivery duct connected to that Connection.

2. The inlet of claim 1 wherein a single temperature control coil is provided to control the temperature of air pumped through the : .. 15 connections. I... S... * S uSe

3. The inlet of claim 1 wherein a respective temperature control coil is provided for each connection. S..

S

* 4. The inlet of claim 3 wherein each temperature control coil is operative to control the temperature of the air pumped through the S.....

* 20 respective connection and into the associated air conditioning duct independently of the air pumped through the other connection(s).

5. The inlet of any one of claims 1 to 4 wherein the or each temperature control coil is mounted on the inlet chamber.

6. The inlet of any one of the preceding claims wherein the inlet chamber is provided with an outlet plenum chamber, the connections connecting the air conditioning ducts, in use, to the outlet plenum chamber.

7. The inlet of claim 6 wherein the plenum chamber comprises a plurality of sub chambers, each sub chamber comprising, in use, a respective connection between an outlet of the inlet chamber and a respective air conditioning duct, each sub chamber being sealed from the other sub chamber(s).

8. The inlet of any one of the preceding claims wherein each connection comprises a tubular connector.

9. The inlet of any one of claims 1 to 5 wherein each connection comprises an individual plenum chamber each of which is in : * s' communication with a respective outlet of the inlet chamber. -S.. S... * . S...

10. The inlet of any one of the preceding claims wherein each connection is provided with a spigot type connector adapted to be sealingly received in the inlet end of a respective air conditioning duct. S. S

*..: * 11. The inlet of any one of the preceding claims wherein the fan coil S.....

inlet chamber comprises pump means operative to pump air through the outlets and through the connections.

12. The inlet of claim 11 wherein the pump means comprises a fan.

13. The inlet of claim 12 wherein the fan coil inlet chamber comprises a plurality of fans, each fan being in communication with a respective connection.

14. The inlet of claim 12 or claim 13 wherein the or each fan comprises a motor which drives, in use, an impellor, the impellor being connected directly, that is without intermediary, to the rotor of the motor.

15. The inlet of claim 14 wherein the motor is electronically commutated, that is, the commutation of the coils of the motor is controlled by electronic control means.

16. The inlet of claim 17 wherein the electronic control means is mounted on the fan.

17. The inlet of claim 15 or claim 16 wherein the rotor of the motor is provided with a plurality of permanent magnets which are driven by a stator that comprises a plurality of electrically conducting windings that are selectively powered in use by the electronic control means.

18. The inlet of claim 17 wherein the electronic control means * .5 comprises a Hall-effect sensor that determines the rotational position of *1S s.... 15 the rotor relative to the stator based on a signal generated by a change in potential difference as the rotor magnets rotate about the stator, the commutation of the motor being dependent on the output of the Hall-effect sensor. S. *

S S...

19. The inlet of any one of claims 15 to 18 wherein the electronic control means comprises an AC to DC converter that converts a mains input (typically approximately 230V) to a DC output voltage.

The inlet of claim 19 wherein a 10 volt DC output from the electronic control means is input to a user operated controller which sends a converted DC signal voltage back to the electronic control means, the electronic control means being operative such that the speed of rotation of the rotor is dependent upon the DC signal voltage.

21. The inlet of claim 20 wherein the DC signal voltage is adjustable using the controller.

22. The inlet of any one of claims 12 to 21 wherein the speed of each fan can be adjusted/controlled independently of the speed of the other fans.

23. The inlet of any one of claims 20 and 22 wherein the user operated controller is adapted to receive input signals from other input means such as at least one of a pressure, temperature, or fluid flow rate sensor remote from the controller.

24. A fan coil air conditioning system comprising an inlet provided with * * an inlet chamber the inlet chamber comprising a plurality of outlets each provided with a respective connection each of which connects one outlet S...

to a respective air delivery duct of the air conditioning system, pump means being provided to pump air through the connections, at least one temperature control coil being provided to control the temperature of air pumped through the connections, each connection being sealed from the other connection(s), such that air pumped through a connection only enters the air delivery duct connected to that connection.

25. The air conditioning system of claim 24 wherein a single temperature control coil is provided to control the temperature of air pumped through the connection(s).

26. The air conditioning system of claim 24 wherein a respective temperature control coil is provided for each connection.

27. The air conditioning system of claim 26 wherein each temperature control coil is operative to control the temperature of the air pumped through the respective connection independently of the air in the other connection (s).

28. The air conditioning system of any one of claims 24 to 27 wherein the or each temperature control coil is mounted on the inlet chamber.

29. The air conditioning system of any one of claims 24 to 28 wherein the inlet chamber is provided with an outlet plenum chamber, the connections connecting the air conditioning ducts to the outlet plenum chamber.

30. The air conditioning system of claim 29 wherein the plenum chamber comprises a plurality of sub chambers, each sub chamber comprising, in use, a respective connection between an outlet of the inlet : ** chamber and a respective air conditioning duct, each sub chamber being S...

sealed from the other sub chamber(s).

31. The air conditioning system of any one of claims 24 to 30 wherein * . each connection comprises a tubular connector.

32. The air conditioning system of any one of claims 24 to 27 wherein * :** each connection comprises an individual plenum chamber each of which is in communication with a respective outlet of the inlet chamber.

33. The air conditioning system of any one of claims 24 to 32 wherein each connection is provided with a spigot connector adapted to be sealingly received in the inlet end of a respective air conditioning duct.

34. The air conditioning system of any one of claims 24 to 32 wherein the means to pump air comprises a fan.

35. The air conditioning system of claim 34 comprising a plurality of fans, each fan being in communication with a respective connection.

36. The air conditioning system of claim 34 or claim 35 wherein the or each fan comprises a motor which drives, in use, an impellor.

37. The air conditioning system of claim 36 wherein the impellor is connected directly, that is without intermediary, to the rotor of the motor.

38. The air conditioning system of claim 36 or claim 37 wherein the motor is electronically commutated, that is, the commutation of the coils of the motor is controlled by electronic control means.

39. The air conditioning system of claims 34 to 38 wherein the speed of 5SIS each fan can be adjusted/controlled independently of the speed of the is 15 other fans.

S S..

40. An inlet substantially as described herein and as shown in the * . : accompanying drawings.

S

S.....

S

41. An air conditioning system substantially as described herein and as shown in the accompanying drawings.

Amendments to the claims have been filed as follows

S

1. A fan coil air conditioning system inlet, the inlet comprising a common inlet chamber which comprises a plurality of outlets, each outlet being provided with a respective connection to connect the outlet, in use, to a respective air delivery duct in the air conditioning system, each outlet being adapted to be connected, in use, to pump means operative to pump air from the common inlet chamber to the air delivery ducts via the connections, the common inlet chamber being adapted to be provided, in use, with a temperature control coil upstream of the outlets of the common inlet chamber to control the temperature of the air pumped through the connections, each connection being sealed from the other connection(s), such that air pumped through a connection only enters the air delivery duct connected to that connection. S * S'S.

2. The inlet of claim 1 wherein a single temperature control coil is provided to control the temperature of air pumped through the connections.

3. The inlet of claim 1 or claim 2 wherein the temperature control coil is mounted on the inlet chamber.

4. The inlet of any one of the preceding claims wherein the inlet chamber is provided with an outlet plenum chamber, the connections connecting the air conditioning ducts, in use, to the outlet plenum chamber.

5. The inlet of claim 4 wherein the plenum chamber comprises a plurality of sub chambers, each sub chamber comprising, in use, a respective connection between an outlet of the inlet chamber and a respective air conditioning duct, each sub chamber being sealed from the other sub chamber(s).

6. The inlet of any one of the preceding claims wherein each connection comprises a tubular connector.

7. The inlet of any one of claims 1 to 3 wherein each connection comprises an individual plenum chamber each of which is in communication with a respective outlet of the inlet chamber. * * S...

8. The inlet of any one of the preceding claims wherein each....

connection is provided with a spigot type connector adapted to be ***.

sealingly received in the inlet end of a respective air conditioning duct.

9. The inlet of any one of the preceding claims wherein the fan coil s..., S...

inlet chamber comprises pump means operative to pump air through the outlets and through the connections.

10. The inlet of claim 9 wherein the pump means comprises a fan.

11. The inlet of claim 10 wherein the fan coil inlet chamber comprises a plurality of fans, each fan being in communication with a respective connection.

12. The inlet of claim 10 or claim 11 wherein the or each fan comprises a motor which drives, in use, an impellor, the impellor being connected directly, that is without intermediary, to the rotor of the motor.

13. The inlet of claim 12 wherein the motor is electronically commutated, that is, the commutation of the coils of the motor is controlled by electronic control means.

14. The inlet of claim 13 wherein the electronic control means is mounted on the fan.

15. The inlet of claim 13 or claim 14 wherein the rotor of the motor is provided with a plurality of permanent magnets which are driven by a stator that comprises a plurality of electrically conducting windings that are selectively powered in use by the electronic control means.

16. The inlet of claim 15 wherein the electronic control means comprises a Hall-effect sensor that determines the rotational position of. * ..

the rotor relative to the stator based on a signal generated by a change in **" potential difference as the rotor magnets rotate about the stator, the commutation of the motor being dependent on the output of the Hall-. effect sensor. S.. * S S...

17. The inlet of any one of claims 13 to 16 wherein the electronic..

control means comprises an AC to DC converter that converts a mains input (typically approximately 230V) to a DC output voltage.

18. The inlet of claim 17 wherein a 10 volt DC output from the electronic control means is input to a user operated controller which sends a converted DC signal voltage back to the electronic control means, the electronic control means being operative such that the speed of rotation of the rotor is dependent upon the DC signal voltage.

19. The inlet of claim 20 wherein the DC signal voltage is adjustable using the controller.

20. The inlet of any one of claims 10 to 19 wherein the speed of each fan can be adjusted/controlled independently of the speed of the other fans.

21. The inlet of any one of claims 18 to 20 wherein the user operated controller is adapted to receive input signals from other input means such as at least one of a pressure, temperature, or fluid flow rate sensor remote from the controller.

22. A fan coil air conditioning system comprising an inlet provided with a common inlet chamber, the common inlet chamber comprising a plurality of outlets each provided with a respective connection each of which connects one outlet to a respective air delivery duct of the air conditioning system, pump means being provided to pump air through the * connections, a temperature control coil being provided upstream of the.1,:.

outlets of the common inlet chamber to control the temperature of air:...:.

pumped through the connections, each connection being sealed from the other connection(s), such that air pumped through a connection only **** enters the air delivery duct connected to that connection. S... S * * S. *

23. The air conditioning system of claim 22 wherein a single temperature control coil is provided to control the temperature of air pumped through the connection(s).

24. The air conditioning system of claim 22 or 23 wherein the temperature control coil is mounted on the inlet chamber.

25. The air conditioning system of any one of claims 22 to 24 wherein the inlet chamber is provided with an outlet plenum chamber, the connections connecting the air conditioning ducts to the outlet plenum chamber.

26. The air conditioning system of claim 25 wherein the plenum chamber comprises a plurality of sub chambers, each sub chamber comprising, in use, a respective connection between an outlet of the inlet chamber and a respective air conditioning duct, each sub chamber being sealed from the other sub chamber(s).

27. The air conditioning system of any one of claims 22 to 26 wherein each connection comprises a tubular connector.

28. The air conditioning system of any one of claims 22 or 23 wherein each connection comprises an individual plenum chamber each of which is in communication with a respective outlet of the inlet chamber. * * S..

29. The air conditioning system of any one of claims 22 to 28 wherein i.'..

each connection is provided with a spigot connector adapted to be sealingly received in the inlet end of a respective air conditioning duct. :.* 30. The air conditioning system of any one of claims 22 to 29 wherein,*** ** the means to pump air comprises a fan.

31. The air conditioning system of claim 30 comprising a plurality of fans, each fan being in communication with a respective connection.

32. The air conditioning system of claim 30 or claim 31 wherein the or each fan comprises a motor which drives, in use, an impellor.

33. The air conditioning system of claim 32 wherein the impellor is connected directly, that is without intermediary, to the rotor of the motor.

34. The air conditioning system of claim 32 or claim 33 wherein the motor is electronically commutated, that is, the commutation of the coils of the motor is controlled by electronic control means.

35. The air conditioning system of claims 30 to 34 wherein the speed of each fan can be adjusted/controlled independently of the speed of the other fans.

36. An inlet substantially as described herein and as shown in the accompanying drawings.

37. An air conditioning system substantially as described herein and as shown in the accompanying drawings. S... * * I... * S *.S.

S * *

I.....

S S. S * S S * SS S... * S 5.. S... S * *

SS S