Dehumdifier

Abstract

A ventilation and dehumidification system comprises an inlet (12, fig. 1) open to the atmosphere; an extraction unit 2 fluidly connected downstream of the inlet and adapted to draw warm air laden with

Description

[0001] This invention relates to a ventilation and dehumidification system.

[0002] Ventilation is required in domestic or industrial buildings, particularly where the ambient air is at least periodically humid or steam-laden. For example, in bathrooms, shower rooms or kitchens, the air can be stagnant, steamy or humid. It is conventional to provide an extractor fan to vent such humid air from the room. Installation of such a fan can be difficult and expensive. In addition, the fan is inefficient, as venting the humid air involves losing heat from the room.

[0003] GB 2614332 A describes a ventilation and dehumidification system that addresses this problem. The system comprises (a) at least one inlet open to the atmosphere; (b) an extraction unit fluidly connected downstream of the inlet and adapted to draw warm air laden with water vapour thereinto from the inlet; (c) a water-cooled heat exchanger fluidly connected downstream of the extraction unit and adapted to cause condensation of the water vapour present in the air passing therethrough and (d) an outlet fluidly connected downstream of the heat exchanger through which liquid water is recovered.

[0004] The system can provide a shower delivery system. Cooling water warmed in the heat exchanger can be fed to a shower head.

[0005] The extraction unit can be arranged to heat the warm air, to cause an expansion assisting in drawing in the air from the exterior to the heat exchanger. Summary of the Invention

[0006] It is an aim of the invention to improve the efficiency of the known ventilation and dehumidification system referred to above.

[0007] Accordingly, the present invention provides a ventilation and dehumidification system comprising (a) at least one inlet open to the atmosphere; (b) an extraction unit fluidly connected downstream of the inlet and adapted to draw warm air laden with water vapour thereinto from the inlet; (c) a water-cooled heat exchanger fluidly connected downstream of the extraction unit and adapted to cause condensation of the water vapour present in the air passing therethrough; (d) an outlet fluidly connected downstream of the heat exchanger through which liquid water is recovered; (e) a thermoelectric device for cooling air exiting the heat exchanger; and (f) a conduit for supplying air heated by the thermoelectric device to the extraction unit.

[0008] The warm air supplied by the thermoelectric device to the extraction unit assists in drawing wet air into the system, reducing the input energy required for that purpose.

[0009] The thermoelectric device may be a well-known thermoelectric plate. In embodiments of the invention, the thermoelectric plate slopes. In this way, moisture on the plate (whether condensing there or in the heat exchanger) can flow down the slope to a drain therefor. The drain may comprise a container including a stopcock for intermittent emptying.

[0010] The heat exchanger can comprise a chamber fluidly connected to the extractor unit, through which chamber the warm air flows, and a conduit for supplying cold water within the chamber. Alternatively, the heat exchanger can comprise a pipe fluidly connected to the extractor unit through which the warm air flows and a means for cooling the exterior of the pipe with cold water.

[0011] In one embodiment, the extraction unit includes an impeller driven by an electric motor.

[0012] The invention further provides a shower delivery system including the ventilation and dehumidification system described above, comprising a shower delivery conduit fed by cold and hot water streams, the cold water stream at least in part being arranged to cool the heat exchanger. After passing through the heat exchanger the cold water stream may feed a tap mixer where it is mixed with the hot water stream before being fed to the shower delivery head. Brief Description of the Drawings

[0013] The invention will now be described in more detail, by way of example only, with reference to the accompanying drawings, in which:

[0014] Figure 1 is an external view of a ventilation and dehumidification system according to an embodiment of the invention;

[0015] Figure 2 shows the system of Figure 1, with part of the housing removed;

[0016] Figure 3 is a sectional view of the system of Figures 1 and 2; and

[0017] Figure 4 is a sectional view of an alternative heat exchanger. Detailed Description of Particular Embodiments

[0018] The drawings show a ventilation and dehumidification system which, in this example, forms a shower delivery system.

[0019] The unit comprises a plastic or metal housing 1 containing a hollow subhousing 2, a heat exchanger 3, a drain stopcock 4 and a tap mixer valve 5 provided with a temperature and flow regulator 6. The mixer valve 5 receives hot water from a pipe 7 connected to an external source (not shown) and warmed water from a pipe 8. The latter pipe is fed from a cooling cavity within the heat exchanger 3 which in turn receives flowing cold mains water or the like from a pipe 10 connected to another external source (also not shown). A shower delivery outlet 13 is connected to the outlet of the valve 5.

[0020] The sub-housing 2 is water-tight and encloses an electrically-driven impeller 11 which draws air into the sub-housing 2 from an air inlet 12 in the housing 1. The impeller also partially heats the air in the sub-housing 2, causing an expansion which impels humid or steam-laden air from the inlet 12 out of the subhousing 2 into the heat exchanger 3 where it surrounds the pipes described above and is caused to cool and condense water entrained in the air.

[0021] This partly cooled air is fed to a chamber 30 containing a sloping electrically powered thermoelectric plate 31. The "cold" side of the plate 31 faces upwards where it is contacted by the partially cooled air and moisture. Further condensation occurs on the cold side of the plate 31. This water drains down the plate 31 and out of the chamber 30 through an outlet 16 that terminates in a drain 4, comprising a stopcock for intermittent emptying.

[0022] The chamber 30 is not airtight, so that air may enter it from the housing 1. This air is heated by the hot side of the plate 31 which carries heat-dissipating fins 32. A pipe 33 leads from the chamber 30 to the impeller 11, which causes the warmed air to flow thereto from the chamber 30 to the sub-housing 2, where it is mixed with the air entering the system through the inlet 12. The warmed air assists in lowering the pressure in the sub-housing 2 and drawing air into the system through the inlet 12.

[0023] If the air exiting the heat exchanger 3 is not fully dehumidified, it can be sent directly back to the sub-housing 2 via the pipe 33 to undergo dehumidification again.

[0024] Figure 4 shows an alternative heat exchanger 3'. In this heat exchanger, the air being cooled flows through pipes 35, whilst the water being warmed fills the chamber of the heat exchanger and surrounds the pipes 35.

[0025] As an alternative to the air inlet 12, the system of the invention can be combined with a shower delivery head of the kind described in GB 2614332 A. Such a shower delivery head includes the air inlet as an integral part thereof. It may have one or air inlet openings located adjacent to one or more water nozzles, and an air inlet line juxtaposed alongside a shower delivery line, which may be a hose.

Claims

1. A ventilation and dehumidification system comprising (a) at least one inlet open to the atmosphere; (b) an extraction unit fluidly connected downstream of the inlet and adapted to draw warm air laden with water vapour thereinto from the inlet; (c) a water-cooled heat exchanger fluidly connected downstream of the extraction unit and adapted to cause condensation of the water vapour present in the air passing therethrough; (d) an outlet fluidly connected downstream of the heat exchanger through which liquid water is recovered; (e) a thermoelectric device for cooling air exiting the heat exchanger; and (f) a conduit for supplying air heated by the thermoelectric device to the extraction unit.

2. A system according to claim 1, wherein the thermoelectric device is a thermoelectric plate.

3. A system according to claim 2, wherein the thermoelectric plate slopes.

4. A system according to claim 1, 2 or 3, including a drain for water flowingfrom the thermoelectric device.

5. A system according to any preceding claim, wherein the heat exchanger comprises a chamber fluidly connected to the extractor unit, through which chamber the warm air flows, and a conduit for supplying cold water within the chamber.

6. A system according to any one of claims 1 to 4, wherein the heat exchanger comprises at least one pipe fluidly connected to the extractor unit, through which pipe the warm air flows, and a means for cooling the exterior of the or each pipe with cold water.

7. A system according to any preceding claim, wherein the extraction unit includes an impeller driven by an electric motor.

8. A shower delivery system including the ventilation and dehumidification system described above, comprising a shower delivery conduit fed by cold and hotwater streams, the cold water stream at least in part being arranged to cool the heat exchanger.

9. A shower delivery system according to claim 7, including a tap mixer for mixing water warmed by the heat exchanger with the hot water stream.

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