Condensate pump assembly

There is provided a condensate pump assembly (100) for use in an air conditioning system. The condensate pump assembly (100) comprises a pump (102) arranged in a housing (104) to pump liquid from a liquid inlet (116) towards a liquid outlet (106). The condensate pump assembly (100) further comprises a liquid receptacle (108) arranged, in a first position in the housing (104), to receive condensate from a condensate inlet (110) and to be in fluid communication with the liquid inlet (116). The liquid receptacle (108) is movable to a second position removed from the housing (104), whereby to empty the liquid receptacle (108). The condensate pump assembly (100) further comprises selective release (112, 114) means operable by a hand of a user to release the liquid receptacle (108) for movement from the first position towards the second position.

CROSS REFERENCE TO RELATED APPLICATIONS

This is a National Stage application of, and claims priority to, PCT/GB2018/052119, filed Jul. 27, 2018, which claims priority to GB Patent Application No. 1712431.4, filed Aug. 2, 2017, the disclosures of which are incorporated herein by reference in their entirety.

This invention relates to a condensate pump assembly for use in an air conditioning system and a kit of parts for forming the same.

BACKGROUND

Condensate pump assemblies are used to pump liquid condensate from appliances that produce condensate, for example an air conditioning system, a condensing boiler system or a refrigerator, out of a room or building. In a typical air conditioning system, the air conditioning unit produces liquid condensate, i.e. water, which drains from the air conditioning unit to a liquid reservoir in the form of a liquid receptacle in a condensate pump assembly mounted to a wall of the room or building, typically below the air conditioning unit. When the liquid receptacle is sufficiently filled with liquid, the liquid is pumped from the liquid receptacle via a liquid inlet and away from the condensate pump assembly, for example outside the room, via a liquid outlet. After sustained operation of the condensate pump assembly, contaminants such as dirt may enter the liquid receptacle and are not removed by the pump. The liquid receptacle can be made removable from a housing of the condensate pump assembly to allow cleaning of contaminants from the liquid receptacle.

In condensate pump assemblies of the prior art, a clam-shell cover is affixed to the condensate pump assembly to secure the liquid receptacle in place in the condensate pump assembly, as well as to act as a sheath to improve the aesthetic appearance of the condensate pump assembly by hiding the liquid receptacle from view. Not only do such covers require two hands to remove, they also increase the size of the condensate pump assembly and create an additional source of noise by rattling against a housing of the condensate pump assembly during operation of the pump.

The present disclosure seeks to provide at least an alternative to condensate pump assemblies of the prior art.

BRIEF SUMMARY OF THE DISCLOSURE

In accordance with the present disclosure there is provided a condensate pump assembly for use in an air conditioning system. The condensate pump assembly comprises a pump arranged in a housing to pump liquid from a liquid inlet towards a liquid outlet. The condensate pump assembly further comprises a liquid receptacle arranged, in a first position in the housing, to receive condensate from a condensate inlet and to be in fluid communication with the liquid inlet. The liquid receptacle is movable to a second position removed from the housing, whereby to empty the liquid receptacle. The condensate pump assembly further comprises selective release means operable by a hand of a user to release the liquid receptacle for movement from the first position towards the second position.

Thus, the liquid receptacle of the condensate pump assembly can be removed from the housing for emptying without requiring a two-handed operation. This is useful because the condensate pump assembly can sometimes be mounted in confined or difficult to reach locations, where it may be difficult to access the liquid receptacle. One-handed operation of the selective release means allows the user to easily move the liquid receptacle from the first position towards the second position for emptying or cleaning of the liquid receptacle. The selective release means is operable one-handed by the user to release the liquid receptacle for movement from the first position towards the second position. It will be understood that the term one-handed does not require one particular hand of the user and in some embodiments, the user may use either hand to operate the selective release means.

The release means may comprise a resilient member biased to hold the liquid receptacle in the first position and movable to release the liquid receptacle for movement from the first position towards the second position.

The resilient member may be provided on the liquid receptacle. The resilient member may be biased to engage with a corresponding lip provided on the housing.

The liquid receptacle may be secured in the first position only by the selective release means.

The selective release means may be operable from a base surface of the condensate pump assembly, when the condensate pump assembly is mounted for use.

A base portion of the liquid receptacle may provide an outer surface of the condensate pump assembly. Thus, the condensate pump assembly need not be provided with a removable cover. The lack of a removable cover reduces the noise of the condensate pump assembly from rattling during operation of the pump, unlike condensate pump assemblies of the prior art. Furthermore, the condensate pump assembly has fewer components since the liquid receptacle and the housing of the condensate pump assembly cooperate to hold the liquid receptacle in the first position, without also requiring a removable cover.

The housing may comprise a shroud portion extending over a side wall of the liquid receptacle, whereby to hide the side wall of the liquid receptacle from view when the liquid receptacle is in the first position in the housing. The shroud portion may extend over all side walls of the liquid receptacle. Thus, a separate removable cover of the condensate pump assembly is not required for aesthetic reasons to hide the liquid receptacle from view when in the first position in the housing.

The selective release means may comprise at least one snap-fit joint. The selective release means may comprise a resilient member biased to hold the liquid receptacle in the first position and movable to release the liquid receptacle for movement from the first position towards the second position. The selective release means may comprise a peg member configured, in use, to apply a force against the housing to secure the liquid receptacle when attached to the housing.

This, in itself, is believed to be novel and so, in accordance with a further aspect of the present disclosure, there is provided a condensate pump assembly for use in an air conditioning system, the condensate pump assembly comprising a pump arranged in a housing to pump liquid from a liquid inlet to a liquid outlet; a liquid receptacle configured to receive liquid from the liquid inlet. The liquid receptacle may be releasably secured to the housing by selective release means. The selective release means may comprise a peg member configured, in use, to apply a force against the housing to secure the liquid receptacle when attached to the housing. The selective release means may comprise a resilient member biased to hold the liquid receptacle in the first position and movable to release the liquid receptacle for movement from the first position towards the second position.

The liquid receptacle may comprise a support member configured to resist bending of the peg member. The liquid receptacle may be configured to be releasable by a hand of a user.

The release means may be operable by either hand of the user. Thus, the condensate pump assembly may be mountable to a wall surface in either of two rotational positions, spaced by 180 degrees, depending on the particular space availability in the vicinity of a connected air conditioning unit. The release means can be operated whether the condensate pump assembly is mounted in a first configuration, or a second configuration, rotated by 180 degrees relative to the first configuration about an axis aligned with a direction of gravity in use. This means the same tooling can be used to produce at least some components of the condensate pump assembly which are suitable for use in either of the first configuration or the second configuration.

The release means may be operable by squeezing. The release means may be operable by squeezing a thumb of the hand towards a finger of the hand. Thus, the liquid receptacle can be easily removed and can be gripped with one hand as part of operating the release mechanism to prevent any spillage during movement of the liquid receptacle from the first position towards the second position.

A shroud portion of the housing may be substantially opaque. Thus, the liquid receptacle can be substantially hidden from view in the first position. A base portion of the liquid receptacle may be substantially opaque.

The pump may be a reciprocating pump. It will be appreciated that other types of pump may instead be used, such as a centrifugal pump. However, vibration of the condensate pump assembly is typically more of a problem with a reciprocating pump than with other types of pump.

The housing may comprise at least one mounting point for mounting the condensate pump assembly to a wall. An axis of reciprocation of the reciprocating pump may be arranged to be substantially parallel to the wall when the condensate pump assembly is mounted to the wall. In embodiments, the housing may comprise a plurality of mounting points for mounting the condensate pump assembly in either of a first configuration, or a second configuration, the second configuration being rotated by 180 degrees relative to the first configuration about an axis aligned with a direction of gravity when the condensate pump assembly is mounted to the wall.

The condensate pump assembly may further comprise a liquid level sensor configured to detect a liquid level in the liquid receptacle when the liquid receptacle is in the first position. The condensate pump assembly may further comprise a pump controller configured to operate the pump when the liquid level sensor outputs a first signal indicative of a liquid level within the liquid receptacle above a level of the liquid inlet to the pump and to stop the pump when the liquid level sensor outputs a second signal indicative of a liquid level within the liquid receptacle approaching or below a level of the liquid inlet to the pump.

The liquid receptacle may comprise a filter to separate a first reservoir from a second reservoir, wherein the condensate inlet is arranged to provide liquid into the first reservoir and the liquid inlet is in fluid communication with the first reservoir via the filter and the second reservoir.

Thus, any contaminants (such as dirt) unable to pass through the filter will remain in the first reservoir and will not be transferred to the second reservoir through the filter. This ensures that contaminants do not enter the pump and cause damage.

The liquid receptacle may comprise a weir in the first reservoir and extending from a base portion of the liquid receptacle. Thus, any contaminants in the condensate liquid having a density greater than a bulk density of the condensate liquid will be caught by the weir and will not even encounter the filter. In embodiments, the liquid receptacle may comprise a weir in each of the first reservoir and the second reservoir.

The liquid receptacle may be formed from an inner portion and an outer portion, whereby to provide a double-walled thermally insulated liquid receptacle. The inner portion may be slidably removable from the outer portion.

The filter may be formed from a resilient material, and flexible such that the filter may be secured, in a bowed configuration, within either the inner portion of the liquid receptacle or the outer portion of the liquid receptacle. Thus, the same filter can be used for condensate pump assemblies both with and without the inner portion of the liquid receptacle.

Viewed from another aspect, the present disclosure provides a kit of parts for assembling a condensate pump assembly. The kit of parts comprises: a housing; a pump to be arranged in the housing and operable to pump liquid from a liquid inlet towards a liquid outlet; and a liquid receptacle for insertion into a first position in the housing to receive condensate from a condensate inlet of the housing and to be in fluid communication with the liquid inlet. The liquid receptacle is movable from the first position into a second position, removed from the housing, whereby to empty the liquid receptacle. One or both of the housing or the liquid receptacle comprise selective release means operable by a hand of a user to release the liquid receptacle for movement from the first position towards the second position.

DETAILED DESCRIPTION

FIG.1is an illustration of a condensate pump assembly with a portion of the housing shown transparent. The condensate pump assembly100comprises a housing104to contain a pump in the form of a reciprocating pump102(not shown inFIG.1) mounted within an anti-vibration motor mount103. The anti-vibration motor mount103is typically formed from rubber. Thus, the anti-vibration motor mount103damps vibration in the condensate pump assembly100caused by operation of the reciprocating pump102. It will be understood that the reciprocating pump102may be damped in other ways, for example through other components connecting the reciprocating pump102to the housing104of the condensate pump assembly100. In some examples, the reciprocating pump102need not use any damping. The housing104is typically formed from plastics. The reciprocating pump102is arranged to pump liquid from a liquid inlet (not shown inFIG.1) to a liquid outlet106. The reciprocating pump102is a well-known pump and the skilled person would readily understand how to provide such a pump. A reciprocating axis of the reciprocating pump102is aligned with a longitudinal direction of the condensate pump assembly100. Thus, a height and a depth (distance away from the wall when mounted) of the condensate pump assembly100can be small. When the condensate pump assembly100is installed as part of an air conditioning system, the liquid outlet106is in fluid communication with a liquid drain (not shown) so that excess liquid can be removed from the air conditioning system.

The condensate pump assembly100further comprises a liquid receptacle in the form of an open-topped, rectangular container108. The container108comprises a base portion and four walls (not labelled inFIG.1). An upper portion of the container108is open to receive condensate from an air conditioning unit (not shown) via a condensate inlet110. In this example, the condensate inlet110is defined by an opening in an upper surface of the housing104. The liquid receptacle108is movable from a first position, as shown inFIG.1, to a second position removed from the housing104. In the first position, the liquid receptacle108is provided at a first longitudinal end of the condensate pump assembly100, opposite an end of the condensate pump assembly100having the reciprocating pump102and the liquid outlet106. In the second position, the liquid receptacle108can be cleaned or emptied of liquid to remove any contaminants from the liquid receptacle108. The condensate pump assembly100further comprises selective release means in the form of a first resilient clip112and a second resilient clip (not shown inFIG.1). The resilient clips112,114can be operated by a user's hand to release the liquid receptacle108for movement from the first position towards the second position. The operation and function of the selective release means will be described further in relation toFIGS.2and3below.

FIG.2is a cross-sectional view of the condensate pump assembly shown inFIG.1. The cross-sectional view of the condensate pump assembly100is taken through a vertical plane aligned along a longitudinal axis of the condensate pump assembly100. Thus, it is possible to illustrate an internal pathway for liquid from the condensate inlet110to the liquid outlet106via the liquid receptacle108, a liquid inlet116and the reciprocating pump102. As will be appreciated fromFIG.2, and also fromFIG.6, described in more detail below, the liquid receptacle108in this example, is insulated. In particular, the liquid receptacle108is formed from a double walled construction, comprising an outer portion109aand an inner portion109b. The inner portion109bis arranged to be removably and slidably mounted within the outer portion109a. Thus, the double walled construction provides thermal insulation of any contents within the liquid receptacle108from an external environment of the condensate pump assembly100. This prevents formation of condensation on an outer surface of the housing104of the condensate pump assembly, particularly in hot and/or humid environments where the temperature difference between the housing104and the condensate within the liquid receptacle108may be significant. If condensation were to form, this may drip off the housing104and be unsightly and unhygienic. In some examples, it will be understood that the outer portion109aonly of the liquid receptacle108may be provided, where insulation is not required (for example in cooler and/or drier environments. When the liquid receptacle108is provided in the first position, as shown inFIG.2, the liquid receptacle108is in the housing104and can receive condensate from the condensate inlet110. The liquid receptacle108, in the first position, is also in fluid communication with the liquid inlet116. In use, liquid, typically condensate water from the air conditioning unit, enters the liquid receptacle108through a drainage tube (not shown) connected to the condensate inlet110. The liquid enters a first reservoir120defined by an internal wall of the liquid receptacle108and a filter118. The liquid receptacle108is also illustrated in the exploded cross-section view shown inFIG.6. The filter118has a length along the surface of the filter in a direction across the liquid receptacle108greater than the distance between the facing walls of the liquid receptacle108. This ensures that the cross-sectional area of the filter118is greater than the cross-sectional area of the distance directly across the liquid receptacle108whereby to improve the capacity of the filter118. In this example, the filter118is formed from a resilient material and has a curved shape relative to the first reservoir120and an overturned lip at a free end thereof. The resilient material and curved shape of the filter118allows the same filter118to be used regardless of whether the liquid receptacle108comprises the outer portion109aand the inner portion109b, or just the outer portion109a. The filter118ensures any particulates in the condensate received from the condensate inlet110do not pass to the liquid inlet116and onwards to the reciprocating pump102. In this example, the filter118is porous to particles of less than 0.9 millimetre in diameter, and is provided by a filter member having a plurality of holes defined therein, each hole having a diameter of approximately 0.9 millimetres. It will be understood that other filter types and/or hole sizes may be used. The overturned lip can be used as a handle to easily remove and insert the filter118relative to the liquid receptacle108, for cleaning and/or replacement. In this example, the filter118is convexly curved relative to the first reservoir120and the overturned lip extends towards the first reservoir120. However, it will be understood that the filter118may alternatively have a concave shape relative to the first reservoir120. The filter118separates the first reservoir120from a second reservoir122. In this way, the first reservoir120is in fluid communication with the second reservoir122via the filter118. In this example, the filter118has a concave shape relative to the second reservoir122and the overturned lip at the free end thereof, extends away from the second reservoir122. However, as above, it will be understood that the filter118may alternatively have a convex shape relative to the second reservoir122. The second reservoir122is downstream of the first reservoir120, arranged to contain liquid received from the condensate inlet110and filtered by the filter118.

The liquid receptacle108is also provided with a weir132,134extending from a base portion thereof whereby to prevent the passage of contaminants having a density greater than a bulk density of the condensate. In this example, each of the outer portion109aand the inner portion109bof the liquid receptacle108is provided with a weir132,134respectively, extending up from a base surface thereof. A height of the weirs132,134is around 2.5 millimetres, and is such that the inner portion109bcan be mounted within the outer portion109awithout significant reduction of the available volume of the liquid receptacle108. It will be understood that the height of the weirs132,134may be greater or lesser, depending on the particles to be stopped by the weirs132,134. In this example, the weirs132,134are formed as two substantially concentric, semi-annular protrusions from the base portion of each of the outer portion109aand the inner portion109brespectively. It will be understood that a different number and/or shape of weirs132,134may be used. Further, the weirs132,134are arranged on both sides of the filter118. The weirs132,134act to prevent the onward passage of any foreign objects or contaminants, having a density greater than a bulk density of the condensate, into the reciprocating pump102.

In this way, none, or at least very few foreign objects or contaminants from the air conditioning unit pass to the second reservoir122of the liquid receptacle108. The liquid inlet116is formed from a hollow tube having an open end and extending substantially downwards within the second reservoir122to a depth below a height of the filter118. The hollow tube enters the second reservoir122of the liquid receptacle108through an open upper portion of the liquid receptacle108. In this example, the open end of the liquid inlet116extends to a position over half of the height of the filter118. Thus, the liquid inlet116can extract liquid from the liquid receptacle108up to a depth of the open end of the liquid inlet116. The hollow tube forming the liquid inlet116is connected, at an end opposite the open end, to the reciprocating pump102. On operation of the reciprocating pump102, the liquid is drawn from the second reservoir122of the liquid receptacle108via the liquid inlet116. The liquid is pumped out of the condensate pump assembly100through the liquid outlet106by the reciprocating pump102. Operation of the reciprocating pump102of the condensate pump assembly100is explained more fully with reference toFIG.5below.

The liquid receptacle108can be released from the first position for movement towards the second position by operation of the selective release means in the form of the a first resilient member112and a second resilient member114. The resilient members112,114are biased to hold the liquid receptacle108in the first position within the housing104. In particular, the resilient members112,114are in the form of a first resilient clip112and a second resilient clip114connected to a side wall of the liquid receptacle108and extending towards a base surface of the condensate pump assembly100. Each of the resilient clips112,114is biased outwardly against a corresponding lip (not shown) provided on the housing104, whereby to secure the liquid receptacle108in the first position in the housing104. The outwardly biased resilient clips112,114exert a pressure against the respective corresponding lips provided on the housing104, whereby to substantially prevent any rattle of the liquid receptacle108in the housing104when the liquid receptacle is secured in the first position in the housing104. In effect, the resilient clips112,114act as a form of shock absorber to substantially eliminate any rattle of the liquid receptacle108in the housing104. A finger recess115is defined in a base surface of the housing104, whereby to allow a finger or thumb of a user to engage with an outer side of the second resilient clip114. By squeezing the resilient clips112,114together using opposing digits on a hand of a user, the resilient clips112,114can both be disengaged from their respective lips at substantially same time, in a single movement of the hand, releasing the liquid receptacle108for movement from the first position towards the second position. The movement of the liquid receptacle108after disengagement of the resilient clips112,114from the respective corresponding lips on the housing104is substantially downwards in use. It will be understood that the selective release means is operable by any one of the hands of a user, and does not require both hands of a user, neither does such operation require one particular hand of the user. Furthermore, squeezing the resilient clips112,114also serves to grip the liquid receptacle108securely in the hand of a user, preventing accidental spillage of the contents thereof. In the present example, the resilient clips112,114can be squeezed between a thumb and forefinger of the same hand for to release the liquid receptacle108from the first position.

In this example, it will be appreciated that the liquid receptacle108is symmetric about a plane of symmetry across the liquid receptacle108and transverse to a direction of liquid flow through the liquid receptacle108. Thus, the liquid receptacle108can be mounted within the housing102in one of two rotational positions.

FIG.3is a further illustration of the condensate pump assembly shown inFIGS.1and2, with the same portion of the housing shown transparent as inFIG.1. In particular,FIG.3shows the condensate pump assembly100from beneath, showing a base portion124of the liquid receptacle108. The base portion124is substantially opaque such that a user cannot see contents of the liquid receptacle108through the base portion124. Furthermore, the base portion124forms an outer surface of the condensate pump assembly100. In normal operation of the condensate pump assembly100when connected to an air conditioning unit, no additional cover is required to support and hide the liquid receptacle108. In this example, the liquid receptacle108is formed from plastics. The liquid receptacle in this example is formed from the same plastics material as the housing104of the condensate pump assembly100.

FIG.4is a yet further illustration of the condensate pump assembly shown inFIGS.1to3, showing mounting portions of the condensate pump assembly. A first longitudinal side wall of the condensate pump assembly100is provided with a first mounting portion in the form of a first mounting point126and a second mounting portion in the form of a second mounting point128. The first mounting point126and the second mounting point128are usable to affix the condensate pump assembly100to a wall of a room or building, below the air conditioning unit of the air conditioning system. Alternatively, the first mounting point126and the second mounting point128can be provided on a second longitudinal side wall of the condensate pump assembly100, opposite the first longitudinal side wall, whereby to mount the condensate pump assembly100after rotation by 180 degrees about an axis aligned with a direction of gravity. In this way, the condensate pump assembly100can be mounted such that the liquid receptacle108is provided at either a left or a right side of the condensate pump assembly100, when the condensate pump assembly100is mounted to a wall of the room or building containing the air conditioning unit. This is particularly useful in space-constrained environments where accessibility to the condensate pump assembly100may be difficult. In this example, the first mounting point126and the second mounting point128are formed from rubber to function as an anti-vibration mount, damping any vibration of the condensate pump assembly100caused by operation of the reciprocating pump102. Furthermore, as has been explained above, the liquid receptacle108can be released from the first position by operation of the resilient clips112,114by either hand of the user. Thus, depending on convenience, the same condensate pump assembly100can be mounted to the wall in either a first rotational position or a second rotational position, rotated by 180 degrees from the first rotational position about an axis aligned with a direction of gravity. The same condensate pump assembly100can also be operated by either hand of a user in each of the first and second rotational positions. This helps to reduce manufacturing costs, since only a single design of condensate pump assembly100need be produced, for a range of different room designs.

FIG.5is an illustration showing internal components of the condensate pump assembly shown inFIGS.1to4. The condensate pump assembly100further comprises a liquid level sensor130configured to detect a liquid level in the liquid receptacle108when the liquid receptacle108is in the first position. In this example, the liquid level sensor130is a dip-sensor configured to output a signal indicative of the liquid level within the second reservoir122of the liquid receptacle108by being responsive to a covering of at least a portion of the liquid level sensor130by liquid in the second reservoir122. In this example, the liquid level sensor130is a capacitive liquid level sensor130arranged to output a signal indicative of the liquid level within the second reservoir122of the liquid receptacle108based on a change in capacitance of the medium in contact with a portion of the liquid level sensor130. It will be appreciated, however, that another type of liquid level sensor may be used instead.

The condensate pump assembly100further comprises a pump controller (not shown). The pump controller may be implemented in hardware or software, or a combination of both. The pump controller is configured to operate the pump102when the liquid level sensor130outputs a first signal indicative of a liquid level within the liquid receptacle108at least a predetermined amount above a level of the open end of the liquid inlet116and to stop the pump102when the liquid level sensor130outputs a second signal indicative of a liquid level within the liquid receptacle108approaching or below a level of the liquid inlet116. The pump controller is also configured to output a warning when the liquid level sensor130outputs a warning signal indicative of a liquid level within the liquid receptacle130above a predetermined warning level within the liquid receptacle108. The air conditioning system is configured to stop operation of the air conditioning unit in response to the warning output.

FIGS.7,8and9illustrate an alternative embodiment.FIG.7is a cross-sectional view of the liquid receptacle200of this alternative embodiment. An upper portion of the liquid receptacle200is open to receive condensate from an air conditioning unit (not shown) via the condensate inlet110. The liquid receptacle200is shown having an inner wall205and an outer wall210sealed together to form an insulating gap260extending around substantially the entire outer surface of the inner wall205. By surrounding the inner wall205the insulating gap260, the insulating effects are maximised and the risk of condensate forming on the outer surface of the outer wall210is minimised. Preferably the insulating gap260is filled with air. However, other gaseous compositions or insulating material may be included within the insulating gap260.

A pair of support members230is also shown extending from the base surface225and configured to secure a filter232within the liquid receptacle200. By placing the filter232in the fluid flow path between the fluid inlet and the pump and securing the filter232such that the filter232extends across the width of the liquid receptacle, larger particulate debris can be prevented from reaching the pump102. The filter232has a length along the surface of the filter232in a direction across the liquid receptacle200greater than the distance between the facing walls of the liquid receptacle200. This ensures that the cross-sectional area of the filter232is greater than the cross-sectional area of the distance directly across the liquid receptacle200whereby to improve the capacity of the filter232. While the filter232is shown comprising a plurality of circular holes, it would be apparent that other shapes of holes may be used. While a pair of supports members230have been shown, it would be apparent that other arrangements may be used to secure the filter232. Such arrangements may include more or fewer than two extending members230. The filter232may be secured to the underside of an upper housing portion107or the base surface225of the liquid receptacle200. A seal is formed between the upper housing portion107and housing104by a gasket135. The filter232may be secured by slots or grooves within the surfaces that define the liquid receiving volume. This filter arrangement may be used in place of the filter arrangement of the embodiment illustrated inFIGS.1to6and vice versa.

The liquid receptacle200is secured to the housing104by selective release means. The selective release means allows the liquid receptacle200to be movable from a first position, as shown inFIGS.8and9, to a second position removed from the housing104. As shown inFIG.7, the selective release means may include a resilient clip215and a peg235at the opposite end of the liquid receptacle200configured, in use, to apply a force against the housing104to secure the liquid receptacle200when attached to the housing104. The force may be applied against an inner surface245of the housing104via an outer surface240of the peg235. The peg235used to secure the liquid receptacle200to the housing105may protrude through a cutaway140. The illustrated arrangement allows a user to remove the liquid receptacle200from the housing104, for example to clear the filter232of debris, by squeezing their thumb and finger together. This means a user is able to remove the liquid receptacle200using only a single hand. For example, the user is able to remove the liquid receptacle200by squeezing together their thumb and finger of their left or right hand. By enabling the removal of the liquid receptacle200with either hand, the flexibility of the present arrangement is further improved. The action of squeezing the thumb and finger together releases the resilient clip215from the housing104and releases a protrusion220of the resilient clip215from the corresponding recess230in the housing104(see alsoFIG.8) used to secure the liquid receptacle200in the housing104. By squeezing the resilient clip215and outer wall210using opposing digits on a hand of a user, the resilient clip215can be disengaged from its respective lip, and in a single movement of the hand, release the liquid receptacle200for movement from the first position towards the second position. The movement of the liquid receptacle200after disengagement of the resilient clip215is substantially downwards in use. It will be understood that the selective release means is operable by any one of the hands of a user, and does not require both hands of a user, neither does such operation require one particular hand of the user. That is to say, the left or right hand of the user may be used to operate the selective release means. Furthermore, squeezing the resilient clip215and outer wall210also serves to grip the liquid receptacle200securely in the hand of a user, preventing accidental spillage of the contents thereof. In the present example, the resilient clip215and outer wall210can be squeezed between a thumb and forefinger of the same hand for to release the liquid receptacle200from the first position. The outwardly biased resilient clip215and peg235exert a pressure against the respective corresponding recess230and inner wall245, whereby to substantially prevent any rattle of the liquid receptacle200in the housing104when the liquid receptacle200is secured in the first position in the housing104. The user's thumb or finger may be received by a slot227in the housing104to enhance the user's grip on the liquid receptacle200prior to squeezing the resilient clip215. The outer wall210may have a protrusion255to further enhance the user's grip on the liquid receptacle200. The thumb or finger of a user may rest on the protrusion255when removing the liquid receptacle200from the housing104. The peg235may be stiffened by a support member250extending from the inner wall205. The peg235may have a first longitudinal axis and the support member250may have a second longitudinal axis and the first longitudinal axis may be substantially parallel to the second longitudinal axis. The support member250may extend the length of the peg235. While a resilient clip215, in the form of a cantilever joint, and peg235are illustrated here, it would be apparent that other releasable joints may be used to secure the liquid receptacle200. While a protrusion255in the form of a horizontal bar is illustrated inFIGS.7and9, it would be apparent that other arrangements to enhance the user's grip on the outer wall210are possible. Outer wall210may include one or more high friction materials to enhance the user's grip on the outer wall210. For example, the outer wall may include one or more rubberised sections. The outer wall may be made from one or more thermally insulating materials, such as plastic.

In summary, there is provided a condensate pump assembly (100) for use in an air conditioning system. The condensate pump assembly (100) comprises a pump (102) arranged in a housing (104) to pump liquid from a liquid inlet (116) towards a liquid outlet (106). The condensate pump assembly (100) further comprises a liquid receptacle (108) arranged, in a first position in the housing (104), to receive condensate from a condensate inlet (110) and to be in fluid communication with the liquid inlet (116). The liquid receptacle (108) is movable to a second position removed from the housing (104), whereby to empty the liquid receptacle (108). The condensate pump assembly (100) further comprises selective release (112,114) means operable by a hand of a user to release the liquid receptacle (108) for movement from the first position towards the second position.