GB2504259A - Magnetic sludge filter - Google Patents

Abstract

A magnetic sludge filter 1 for a wet central heating system, the filter comprises a vessel 2 with a recess 3 extending internally within a cavity of the vessel and a magnetic element 4 located in the recess wherein it is external of the vessel. The filter has a means to direct fluid flow into the cavity about the recess whereby magnetic particulate matter in the fluid is attracted to the recess. A manifold (lid / cover / top) 6 is securable to and separable from the vessel wherein upon separation of the manifold from the vessel the magnet is retained with the recess. The manifold comprises a valve arrangement 9, 10 connected to and isolates the filter from the heating system. A seal may be between the vessel and manifold. The recess may be centrally within the vessel and may be rectangular. Detents 11 may interlock the magnet in the recess. The magnet may comprise a plurality of stacked magnets. A vent valve 14 may permit air and/or fluid pressure to be removed or relieved from the vessel.

Description

The present invention relates cenerafly to magnetic udae fitters and mot'e oarticulav to magnetic siuo9e Mere fOr wet central heating systems, Wet central heating systems are wellknown and use water has medium to take heat from a bolter to radiators using gravity and nornI&y a pump to drive flow. Some wet central heating syterns use a header tank to ensure a head of water is maintened in the system but more ac recently ck'sed systems have.bBen provided with for egam e a combi-boer. Whether an open system or a otosed system it wiil be aopreciated that the water in the wet system is subject to fou]ng for xample from nstatlahon matenals such as sober flux ace corroson products of pipes, olnts, radiators etc. in the system. The particulate matter in; the central heating flew can be referred to cotlectiv&y as magnetic sludge. A significant proportion of such magnetic sludge at least is susceobbie to magnetic interaction so -a range of magnetic siudge filters or collectors have been providad in which a magnet is located in a vessel so that the magnetic skrdge is attracted to the magnet and so mmoved from the flow.

The magnets are integral within a prior magnetic sludge filter so typcally the whole filter or magnetic assembly needs to be' removed from the system so that the magnetic sludge can be ds:posed of by flushing the magnet directly and ft has been difficult to tune or provide magnets for parhcul-ar eftuations or dosing with particthar dosing agents to act as inhibitors to corrosion within the wet cenfrs4. heating system.

23 bn accordance with first aspects of the present invention there a provided a magnetic Sudge filter for a wet heating system, the fflter comprising a vessel With a recess extending internally within a cavity ci the vessel and a separable magnetic element located externally within the recessr the filter having means to direct a fluid flow in use into the cavity about the recess whereby magnetically inducible oarticulate matter in the flow is attracted to the surf ace of the recess.

In accordance with second aspects of the present invention there is provided a niagnebc sludge filter for a wet heating system. the fitter o mprising a vessel with a recess extending nternaily within a cavity of the vessel and a magnetic element comprising a probe to extend from the extenor r.to the recess, tne probe having apertures to receive magnetic eements edge to edge in a stack in the direction of the probe.

in accordance with third aspects of the present invention there is provk$ed a magnetic &ucIce fifler for a wet heating system. the filter cc-mpdsinq a vessel with a recess extending internafly within a cavity of the veesci and a magnetic element, the filter having a vane eteMing towMds the recess across the vessel and in association with a msnifod for closure of the vessel, the rnan3foid having an inset and an outlet with the vane extendng between them to act as a baffle o direct flow of a fluid in use between the inlet and the outlet.

Further in accordance with sonic aspects of the present invention the filter may have a separsbk vessel and manifold. The manifold may have an mist Valve and outlet valve with each. valve operable in use to leaSe the filter from the heating system. The separable vessel and manitod may have a sea between them, The sea may comprise an inner seal and *nutar seil. The seals may be C) rings or IIet:5eals The manlfofrJ s associated with the vessel by? screw thread, he vessel may ha a canister or cartridge with a transportation and/or storage seal to retain a dosing portion within and the seal removable or disp1ceabie prior to and/or upon assocra:on vnth the manifold.

Further in accordance with some as&?ectsof the present invention the recess may be central within the vesseL The recess may be reciproSly shaped to envelope the magnetic element, The recess may have a rectangular crossaection. The recess and the meonetic Sement may have an interference inter-lock association to retain location of the rnaonet;c element within the recess An inner swiace of the recess may be shaoed to increase surface area erposed to a fluid flow in use. The inner surface may be undulating or ribbed or have 23 caeteliation.s. The inner surface f the recess may have a separable removable disoosabis cover to help cleaning. protection and/or to facilitate naterdion of sludge. The disposable cover may be adhesIve to further capture particulate matter. The dieposaLt cover is removable from the recess, the recass m'y be transparent. The eisposle cover may be transparent. The disposable cover may be arranged to sag in use as particulate matter is associated with the d.;sposable cover and/or recess under attraction tote magnetic eisrnent Further in accordance with some aspects of the present invention the magnetic element may comprises a frame to receive a piuraMy of magnetic parts edge to edge. The magneilo parts may be discs. The magnetic parts may be made from rare earth Neodymium magnets. The magnetic element may have different cornthnations of magnetic parts associated with the element to provide a desired magnetic performance for the magnetic element in use within the recess and the vessel, The poles ci the magnetic eieme.nts may be orientated so that the axis of the magnets s perpendicular to the axis of the vessel so that the effect of the magne&' field:n attracting magnetic particulate matter is maxiniseci. A plurality of magnetic &emarg's may be provided as a kit for a rnanetic sludge filler, each megnetto element s ha*g a citfierent performance in use. The recess and ma9natic element may be matched by configuration and/cr az for a particular combinaflon, The magnetic element may be matched by colour to a type of filter, a vessel type, a heating system type and/or size or a chemical/inhibitor type. The maanetFc parts may be stacked edge to edge in pairs with juxtaposition of opposite magnetic paSs. Typically, two magnetic parts may be provided with apposite poles next to each other in a stack for magne:bc attraction with particulate matter in a fluid flow through the filler and for location in The frame, Further in accordance with some espc4cts of the present invention the vessel may udude maings indicative of voluma The vessel may include an insect to wiry the vaume of the vessel. The insert may inciude a poclet to receive a solid element, The insert may float within the vessel. The insert may float when the sSid &ement has dissdved, The magnetic element may be configured by parts orientated so that the magnetic axis of eah or is perpendicular to the axis of *h vesse/ whereby the maqnetic field for attracting magneho partculat mater s provde about the recess and naxmsed.

in accordance with a fourth ascect of the present invention there orovided a meonetic sludge filter for a. wet heating system. the filter comprisinc a vessel and a agnetic element externally mounted with a recess ci the macel.,. the vessel associated with a manifold having a valve oper'abe to remove air from the vessel.

The valve may be a pressure relief valve, The pressure relief valve may be arranged to operate to open one way when a pm-determined pressure 1s reached in the vess& The valve may be manually operable and/or automatic.

Embodiments of the invention will now be desenbed by way of example only with reference to the accompanying drawings in which: Figure is a schematic illustration of a magnetic sludge filter in accordance with aspects of the present invention: Figure 2 is a front elevation of a magnetic sludge Mer: and Figure 3 s a crosssection of a magnetic Sudge filter in accordance with panicular aspects of the pre ant invention.

Wet central heating systems generaily use water as a fluid pumped or driven around pipe S work to radiators from a boiler whh a thentostat and other controls to regulate operation.

Various parts of the heating system may rae{Jit in paricuffite matter n the system. For ekampie parts of the radiatora and botier may be ferrous so that corrosion may create a characteristic. magnetic sludge in the heating system. it is noniial to add an inhibitor generafly in the form of a sotution or ilnuid chemic& portion to a desired dosing ?eve but such inhibitors are not absolute and a certain level of magnetic siudge is inevitable particularly with wates having certain characteristics including hardness values and acidity levels, the use of dissimilar metals in contact. and same dissolved oxycen from adentthous air ingress. The magnetic sludge should be removed to maintain the efflcSnci of the a-stem ad iife of components.

Being fenous it will be appredated that it is known to provide a magnetic &eruent which extends through a header cap into a flow vessel at a prior magnetic sludge filter in ordet to attract the magnetica#y inducible particulate matter to it. The tiessel is connected to the heating system with an lniet and en outlet with a cumbersome process needed to remove the magnetic sludge or paflicuiate matter invoMng releasing the magnetic etement with the cap and then draining the vessel thorough a drain valve at the bottom of the vessel The orocess is messy. time consuming and it wili be understood that once the maqnetic element is removed the magnetic sludge is released into the vessel rather than kept in a tight concentration near to' the magnetic etement. In stch circumstances a part of the released magnetic sludge may he returned to the heating system by gravity and siphoning effects.

Aspects of the present invention provide a magnetic sludge filter for a wet central heating system in wtftc.h the magnetic sludge can ic retained within a flow vessel until disposai and flusltig of the vessel. Figure 1 provtdes a schamatic iilustraton of a cro secton of a magnetic sludge filter I in accordance with aspects of the present invention. A first aspect is the prcvl:sion of a readily detachable flow vessel 2 with a recess or pocket 3 extending info the vessel 2. The recess 3 accommodates a magnetic element.4 externally but which also extends into the vessel 2. A second aspect of the present invention is that the magnetic element 4 comprises a frame with a plurality of magnetic parts in an edge to edge stack in a pate to opposite pole orientation. By the second aspect the magnetic element $ can have a much greater magnetic flux density itt comparison with prior magnetic elements. A third aspect of the Invention relates to provision of a vane which extends across the vessel generally aligned with the recess 3 and extending towards the recess 3. The vane S is generally part of or associated with a manifoid 8 such that a fluid flow shown by arrowheads can flow from en inlet 7 to an outlet 8 past the recess 3 rather than directly between them.

As seen normay the vane 5 does not extend completei to contact the recess 2 as this is mnecessary to urge desired flow past the recess 3 such that by magnetic attraction inducible pafliculate matter can become associated and adhere to an inner surface of the recess. AU of these ascecta along with other features as described below may be included together or separately in a magnetic sluage filter in accordance with aspects of the present nvenbon.

The manifokl 6 and the vessel 2 are associated bether in operation with normally a screw thread and seals. an inner 0 ring sea ana an outer gasket seal as described iater. The inlet 7 and the outlet $ have a raspeotve valve 9, 10 which can be shut or dosed to flud flow and so eectively ate the magnetic sludge filter I frern the remainder of the heatin2 syslem.

In such circumstances it will be appreciated that with the valves closed then the ss& 2 can be detached from the manifold $ with the magnetic element 4 still within the recess 3. In such circumstances the magnedo element $ will ensure that magnetically induced particulate matter remains adhered to the inner surface of the recess 3 under the attraction of the magnetic element 4, the liquid in the. vessel 2 can be poured away. then the magnet element 4 removed and the vessel 2 then flushed fri Cr1 appropriate manner to remove 15 now ass adhered paticuh e matter (magnetic attraction from th.e rnagnetio element has been removed) from the inner surface of the recess 3.

The recess 3 and the nla2netic element $ are shaped and sized so that there is a reciproc association. The magnetic. element 4 will normally be a ciose fit wittun the recess 3 to maximise the magnetic fleic and flux for attraction of parouiate matter and so that there is interference for retention of location of the magnetic element in the recess 3 and so the magnetic sludge filter 1. Orientation of the magnetic element 4 and magnet pars therein is key to maximizing use of the field to catch as muth magnetic sludge as possible. The majnet parts and magnet element will generally be aligned with The major longitudinal direction of the major part of the recess and typically the vessel so that the parts are edge to edge, pole to opoosite pole to maximise magnetic flux substantially perpendicular to that axis for ettracton of sludge particles in the fluid flow. To ensure or further ensure appropriate locabon and retention of that location in the recess 3 normally some form of interlock is provide sc in the example illustrated in figure 1 reSpeCtRte detents 11, 12 are provided to interengage wfth eath other un'ess a d[sptacement fote is applied to push the n'agnetic element 4 into the recess 3 or pu the magnetfo element 4 out of the recess 3. The meonet element $ wW be formed wfth parts such that the edges of adjacent and so poles of the magnet pats are aigned pS to opposite io in tine to increase available magnetic flux or S sludge attraction in the fitter.

The recess 3 is normally centrafly located Mt*hin the see 2 and so in the main iluid flow between the intet 7 end the outlet S. However. it will be appreciated t*.ht more than one recess and so magnetic-element could be pmvided in the same vessel for respective interaction with the fluid flow.

It wi be appreciated that there may be situations where different >ev&s ot maanetic interaction with the fluid flow may be desirable. For a ample at iniU& heating system -set up or wten the stem has been subJect to a flush with flushing solution then more rapid iS removal of magnetic sludge may be desirabe. In such circumstances -the magnetic S!nent 4 may be pushed futthe.r into the recess 3 than normally so a great& part çr the inner surface of the recess s then available for adhesion of particulate matter under the hfluence of the magnetic element or sirripiy a more powedul magnetic element. or a greater number of maunetc eements mtroduced. sn either event it wth be appreastec on a u<e or uke oasis more magnetic sudge will be removed in a quicker time returning the heating system to e-quilitrium.

In the nonnal course or events the vessef 2 and the magnetin element 4 will he matched for a pattcular heating system. The vessel 2 will have a size adequate to act as a magnetic sludge filter for the associated heating system; it wiil be understood that a four radatar systeni wili gen emily not generate as much magnetic siudge as a twelve radiator system The size of the magnetic sludge filter may be a drag on the pump for the heating system. In such ciro ustances the reass far each veesd will be sized and shaped so at it will only sominodate end retain in position magnetic atementa of a pantular size -and conhquration so ensuring that the correc magnetic &erent is used. Furthermore the vessel 2 and the magnetic element 4 could be matched by colour so that the correct combination is used.

The vessel 2 will normally have a volume in the order of a 2%Omt or 500mi as a definition of a desired singie dose of inhibitor chemicals and so may provides a convenient means of access to dose the heating system with an inhibitor c-herr-ic-al, This could be particularly useful in systems which do not haie a header tank, The vessel 2 as indicated -acts to allow a throuch flow when associated with the manifold. The vess& 2 cotdd be canister or cartridge ore-loaded with an inhibitor chemical A magnetic sludoe fiRer 1 in accordance with npects of the present invention ae,dfrated S above wifi have the manifold 6 assodated with the vessel 2 with a head unit to connect them. The manflotd 6 eHows the titer I to be scured throuch the inlet 7 and outlet 8 to the heating system pipe work. The vessel 2 in the form of a canister provides means for flow about the recess 3 and hence the extemahy associated magnetic Sment 4. A fluid ght association must be provided eMen the head unit of the manifold $ and the vessel 2 and this is generaily done ith a screw thread and appropriate seais The magnetic element $ is generally a plastic-frame or tray to recSe magnetic p-ads such as pairs or stacks of disc magnets formed from a suitatde material e.g. Neodymium rare earth magnets. The discs are edge to edge. pole to opposite pole.

It will be understood that the magnetic sludge Thier 1 by necesafty needs to be robust so an appropriate material will he used for the manifold 6, the eesei. 2 and any retaining ring (not showi in figurel}. Suitable materials include a cast austenitic stainless stee, for example etS number 14301 Hated in BS100$6-i:2005 or an equivalent (such as the farmer designation 04i. An all metal structure is preferred to a plastic structure to provide greater durabthty and long term htegity. However, the magnetIc element 4 will tend to be a plastic frame to allow easy o mounting and presentation of the magneto elements in the recess 3.

The inlet 7 and the outlet S as indicated above generalty have SL1e3 9. 10 respectIvely tO allow isolation of the filter I so that the vessel 2 can be readily removed. These valves 9. 10 2 may be integral wfthin the inlet 7/outlet $ or separate but in either arrangement provide norm-ally through compression type fittings connections to the remainder of the heating system.

TM vessel 2 end the magnetic element 4 are removable from the manifold 6/header macthor so that the magnetic sludge paniclea remain enthralled with the magnet element 4 through the wells of the recess 3. The element 4 reruSna in place through an interference lit andtor an interlock arrergement ii so it can be separated. ]t wifl also be understood that a handle or}cnob 12 will normafty be provided at one end of the magnetic element 4 to allow manipulation of the element 4 into and out o the recess. Such a handle 12 may also allow the element 4 to be turned periodically and/or adjusted in and out at the recess if necessary.

B

The vessel 2 is moulded or cast or shaped to provide an nternai central rectangular recess 3 for reception of me magnetic element 4 though an opening in the base of the vessel 2 By provision of an nternai1y extending recess tt wfll be noted that the recess can be centraRy ioceted with the magnet compared to prior arrangements whefe the magnet element was attached to end protruded fran the side of the bowL Such externei mounting of the magnetic element into a pocket recess aftows magnetic flitering out of the magnatc* sludge to adhere to the inner ewface of the recess without direct contact vth a fixed magnetic element. Such an assocSon allow disassemblv with the magnetic element and then flushing along 4th to greater flSthty with respect to magnetic elemeni. design along with other elements o1 the meonetic aJudge filter, The magnetic element traps magnetic material in the fluid flow but the maanec element may be rectangular or at least the frame for magnetic parts can be rectangular with those magnetic parts assembled in a variety of magnetic forms. The magnetic element can therefore b. riesioned in a rectangular farm OT otherwie so that the magnetic parts and hence the magnetic!.iS is presented to a fluid twater) flow in the heating system to optimise magnetic attraction of suspended magnetic particles with

magnetic fields orthogonal to fluid flow.

A rectangular magnet housing forthe magnetic element allows options for presenting the magnetic field to the fluid flow with restricted 110W PaSt the Short side and unrestricted flow past the kni side, Thus, as oescribed in a preferred entodhnent end in accordance with second aspects c the p'esent invention a magnetic element 4 is provided comprisino two oairs of magnetic parts in the form of discs. It MU be apprecIated that other forms and numbers of magnetic parts is possible. The magnetic perth are aligned in a frame or housing with opposite OiBS side by side or edge to edge in order to enhance and amoiifv the magnetic attracbo coo also as opposite poles attract a hght pastc frame s ad that s neen to retain the magnetic parts together as they are attracted to each other.

It will be underatood that whilst it is advantageous to render the vess& 2 separable from the 3D manifold 6 it s important to maintaIn the integrity and operation of the tUtor 1. 10 such cltcunlstancas as deacribso above the vessel 2 is either attached directly by a screw thread association. Alternatively, a screw thread collar is provided to eitend between the vessel 2 and the manifold 6 ever external threads. t3y such a configuration the screw thread collar will ensure that the screw thread does not come into contact with the fluid of the central heating system and so wiB not suffer problenis & seizure after long periods. Tb further restrIct such seaure problems as described previously a double seal approach is advantageous in that a gasket seal is provide about an outer associatkn between the head or manffold $ and the screw thread tanfrg collar and. an C) ring seal provided as en inner sea] in contact wfth or wetted by the f'iuid of the wet central heating system. it will also be understood that by usng a ratainino ocUar the rather than applying force to the vessel itself to demou't the vessel 2 the releasing forces are apphed to the collar or retSnng ring causing less disturbance of the vessi 2 and of scattering or r uease of adhered/trapped magnetic partides taken from the fluid flow. The vessel 2 and the magnetic element 4 are removed together with the fluidrapped magnetic sludge. The fluid is removed by inverting the vessel 2 with the magnetic element 4 still in piece within the recess 3. The magnetic element $ can then be :10 withdrawn from the recess 3 in the vessel 2. The trapped magnetic sludge can then be rinsed from the vessel 2 with the magnet element 4 withdrawn and under better controlled conditions reduclng mess and waste.

The provision of valves 9. 10 allows the filter I to be isolated in a heating syslem or posably fluid flow in the heating system to be diverted Mto a by-pan in either event the 2 can be removed and magnetic sludge flushed out. Furthermore in accordance with aspects of the pmsent invention the vessel 2 can seen as a convenient way of dosing an effectively closed wet heating system such as used for example with combination boers. As background it wIll be understood that traditional gravity fed boiler arrangements have a header tank and so this header tank has provide a convenient it lneflhenr means of inttcaudng inhibitor chemicals to a heating systems. in modern systems generally the header tank is reciaced with an expansion tank as the heating sjstem is dosed. In such circumstances it is cuite normal to introduce the inhibitor chemica] through any convenient means suth as identifying the highest radiator and partialiy draining the system so that inhibitor chemicals car be introduced through a funnel into the bleed plug of the radiator.

Clearly this is not ideal but avoids a more substantial drain dovm of the system.

With a separable VCSSCi 2 it will be understood that this vessel 2 may be loaded or fiiiea'wilh.

a dosing portion of inhibitor chemical after removal of magnetic sludge. Thus, by rendering the vessel 2 separable through the valves 9, 10 an easy approach to irtrodudng inhibitor chemical is achieved, Furthermore, more surety that the correct dosage has been introduced can be achieved. The dosage can be measured into the vessel dependent upon the size of the heating system and with more aDecification along with accuracy to the partictdar fluid volumes in the system reducing use of chemicals and costs. Alternativeiy, the veseci itself can be a measure either through. graduations or markings for volume in the vessel or the vessel having a known volume so when fully filled that volume S chemical 15 introduced to the system. Typically the vessel 2 will be des ned to have a vohjnle at least greater than 250 nil so that the vessel 3, can faoilitate dosing of inhbitor chem)cals in.250rn1 quantities.

it wtU also be understood that an insert may be provided within the vessel 2 which changes S its volume to that requied in terms of a dose of inhibitor chemical or provides a meazs to present mhib.ttor Lhernica in a solid form to dissolve as required and pos&bIy to an extent necessary for the heating system when the fl:fter is ra-ettathed to the heating system and fluid flows again.

A vent 14 is typically provided within the header part of the manifold 8 for venting any air withm the vessel 2. Furthennore the vent 14 may be used to extract small samples of heating system fluid f& testing in terms of condition and inhibitor effectiveness by laboratory analysis, on site chemical testing or dipping of electronic teat devices. The vent normeHy be a valve which may also he pressure relieving with manual or automatic control y providing the recess 2 and the magnetic &ernent 4 towa4s the bottom of the vessel 2 ft will be understood that means are needed to ensure the recess 3 is washed by a substantial ropcrtion of the heating system fitad flr in accordance with third aspeoS of the present invention the vane 5 protrudes towards the recess 3 to direct flow over the central recess 3 and so near to the meenetia elament 4. Magnetic earticles in flow wiH then be attracted by the element 4 so that these magnetic particles adhere to the inner surface of the rsces 3. The vane S is ticaily fiat and rectangular across the vessel 2. The vane S acts as a flow divider or baffle to inhibit direct flow between the inlet 7 and the outlet V o diverting some flow at Least towards the recess 3.

The va= fi may be acsonited with fittinas to facilitate a power flushinq action within the vesSei 2 when tne inlet 7 and outlet B are closed. The vane 5 could be attach to a sutabiy deiigned fitting in place of the ceriiter and the vane CS employed as a blanking plate separating the in and out flow thannels. Tha flttlng would have hose or other attachments for connecting with a power flushing machine, and hence provide a simple and affective means of connecting the system with a power flushing machine for cleansing the system {not the canister or vessel of the filter).

Figures 2 and 3 show further aspects at the present invention in a mare practical form with consistent reference norre-nolature used tar comparison with figure 1 In such ctumstance k5 will be noted in the front elevation depicted n figure 2 a vessel 2 in the form of a cartter or carbidge is provided and secured in sedation with a manifold through a retaining ring or collar 6a. The manifold 8 has an inlet 7 and an outlet 8 to allow the msnehc sludge filter 1 to be secured tc a wider heating system cnot shown). The retainina rini or collar Ca acts through a screw thread to bridge external sçrw threads in the respective vessei 2 and manifold 6. A handle or knob 12 part of a magnetic Sement (not fully shcwn extends below the vessel 2. The knob 12 Slows inse.thon and retraction of the magnetic etement 4 as rsquwed, The manifo:d 6 includes a pressure relief and aIr and aampllng vent 14 in the OUtlet part of (ho manifold.

Figure 3 provides a cross echon of the magnetic sludge filter I shown in figure 2. Thus, the veset 2 is secured to the manifold 6 by a retaining collw or ring Ca with a vane 5 extendirn into the vessel 2 towards a recess 3 in the vessel 2, Within the recess S a magnetic element 4 is located and secured by an interference fIt and/or an interlock detent 11 towards an opening SPId vi the recess 3. As described previou&y a fluid flows from the inlet 7 to the outlet 8 through the vessel 2. The vane S ensures that a more significant proxnrtion df inc flow is forced near to recess 3 and so the magnetic element 4.

The magnetic element $ comprises a frame made of plaflc with apertures 21 to receive respective magnetic parts Uiot shown) in opposite pole to opposite pole configuration to mnaximise the magnetic field. In the example llustrated the apertures are circular to accept magnetic parts in the form of discs. In use the heating system fluid wilt flow about The recess 3 so that with the. Giernent 4 within the recess 3 it will be appreciated those magnetic-paPicles will be attracted and adhere to the inner surface 3a of the recess 3 and will remain attracted whilst the element 4 remains within the recess 3.

It wH be appreciated by those skilled in the art that any number of combinations of the afommentioned features and/or those shown in the appended drawinqa provide clear advantages over the prior art and are therefore within the scope of the invention described herein.

Claims (25)

1. Claims A magnetic Sudge filter fo a wet heating system, the iiIt& comprising a vessei with a recess exlendin.g intarnaily within a csvi' of the veee& and a separable magneic. element S ocated externally within the recess, the fIUer having means to direct a fluid flow in use jOb the cavity about the recess whereby magnecay inducible parttcuiale matter in the flow is attracted to the surface of the recess.
2. 2. A magnetic &udce filter for a wet heating system. the filter comprialno a vessel with a recess extending internally within a cavity of the vessel and a magnetic element comprising a orabe to extend from the exterior Thto the recess, the probe having apertures to receive magnetic eicments edge to edge in a staci in the dinaction of the probe.
3. 3. A magnetic sludge filter for a wet heating system, the filter comprisfng a vessel with a l recess extending internally within a cavity of the vessel and a magnetic element, the filter having a vane extending towards the recess across the vessel and in association with a manifold for closure of the vessel, the nianfloid having an inlet and an c-utlet with the vane extendinq between them to act as a baffle to threct flow of a fluid in use between the inlet and the outlet. "C.
4. 4 A filter as claimed in any of claims I to 3 cherein the filter the vesse! end the manifold are separabe with the senarabie magnetic element withn the recess.
5. 5, A filter as clalmed fri claim 3 cc claim 4 wherem the manifold has an inlet valve and an outlet valve with each valve operable in use to isolate the filter from the heating system.
6. 6. A filter as claimed in any of claims 3 to 5 wherein the separable vessel and manifold have a seal beeen them.
7. 7, A filter as clamed in daim B wherein the seal comprises an inner seal and cser seal.
8. 8. A fitter as claimed in claim 7 wherein the seals are U nngs or gasket seals.
9. 9. A filter as claimed in any of claims 3 to wherein the manifold is associated with the vessel by a screw thread.
10. 10. A filter as laimecf in any proceeding ciaim wherein the vsssel is a canister or cartridge with a transportation anOJor storage seal to retain a dosing portion within and the seal removable or displaceable prior to and/or upon aociaticn with the manjfolo.

    S
11. ii A filter as claimed n any proceeding daitii wherein the recess is central within the vesei.
12. 12. A filter as claimed in any proceeding claim wherein the recess may be ciprocaBy shaped to enveloe the. mgneflc element.
13. 13. A filter as claimed in any proceeding claim wherein the recess has a rectangular crosssecthjn.
14. 14. A filter cc cakned in any proceeding claim wherein fh recess and the separable i magnetic element have an interference inter-tack as.sociaiion to retain location of the magnetic element within the recess,
15. 15. A filter as caimed in any proceeding claim wherein an inner surface of the recess is shaped to increase surface area exposed toe fiukt flow En tse.
16. 16, A fter as claimed in claim 15 wherein the hiner surface is undulating or ribbed or have castelatiots.
17. 17. A filter as claimed n any proceeding claim wherein the inner o th recess 2 has a disposable OQVCI.
18. 18. A fiRer as claimed in ciaim 17 wherein the disposahie cover s removable from the recess.
19. 19, A filter as clabned in any oroceeding claim wherein the recess is transparent.
20. 20. A filter as clsimed claim 17 or claim 18 wherein the disposable cover is transparent.
21. 21. A fitter as claimed in any of claims 7, 18 or 20 wherein the Asposabie cover i arranged to sag in use as partIculate matter is associated with the disposabie cover and/or recess under attraction to the magneUc element
22. 22. A filter as claimS in any proceeding claim wnerSi the magnetic element comprises a frame to receive a c4urailt' of magnetic parte edge to edge.
23. 23. A fitter as claimed n claim 22 wherein the magnetic parts are discs.
24. 24. A fi&er as cialmed in cla/m 22 or claim 23 wherein the magnetic parts are made from Neodymium rare earth magnets.
25. 25. A filter as daimed any of cEaims 22 to 23 wherein the magnetic: element can be Lonngured to nave thfferent carnoinahons of magnebo parts assocated wgh the eternent to provide a des?recI magnetic oerarmance for the megnetc element n use eethn, the races end the vessel.4S. A fiter as daimed in any pocoading claim wherein a piuraty of magnetic elements can be provided as a kit for a magnetic sludge filter, each magnetic element having a diflereirt perltrmance n use.2?; A fitter as claimed in proceeding dairn wherein the recess and magnetic element are matcthed by conngurahon and/cr szs for a partcular com:bmbon 2.5 28. A filter as.caimad i:r'. cldm 27 wherein the magnetic element is matched by colour to a type of filter, a vessel type, a heating sytem type enct/w size or a chemicauinhbttor type.28. A fitter as claimed in claim $2 and any claim dependent thereon wherein the magnetic parts are stacked edge to edge tn pairs or more and with juxtaposition of opposne magneto potes to amplify the magnetic flux aveilabe for mognebo attraction with particular matter in a fluid flow througn the filter.sa A filter as dairned in claim 29 wherein Mo magnetic parts are provided with. opposite poles next to each other in a stack for magnetic attraction with particulate matter in a flL flow through the filter and for location in the frame.31. A fiber as claimed in any proceeding claim wherein the vessel includes markings inthcative of volume 32. A filter as claimed in claim 3'i wherein the vessel includes an insert to change the S volume of the veesel fcr an inhibitor chemical.33. A ?iter as claimed in otaim 31 or claim 32 wherein the nsert includes a ocket to receive a sod element.:10 34. A filter as claimed in any of cialn 31 to 33 wherein the insert is buoyant and floats within the vessel when S of fluid in use.3. A hiter as claimed in claim $4 wherein the insert floats when the solid element has dissolved, t5 3(3. A filter as claimed in any proceeding claim wherein the magnetic element is configured by pats odentated so that The axis of each pact is persnthcular to the axis of the vessel whereby the magnetic field for attracting magnetic particulate mater is prtMde about the recess.37. A filter as claimed in any prooeeelng claim wherein the vessel includes a vaNe to allow air and/or fluid pressure to be removed or relieved in the vessel and/oc a heatino system in use.2 39. A sludge filter for a wet heating system. the filter cemrising a vessel and a magnefic element externally mounted with a recess of the vessel, the vessel associated with a nianWold having a valve operable to remove air from the vessel.39. A filer as claimed in claim 38 wh'ein ihe valve is a pressure relief valve.A filter as claimed in claim 39 wherein the pressure relief valve is arrangjed to operate to open one way when a predetemiined pressure is reached in the vessel.$1. A filter as claimed in any of claims 38 to 40 wherein the valve is manually operable and/or automatic, 42. A rnagnetc sudge fi1r for we heaVng system suhstarUaffv as hernhfore descñbed wth reference to the accompanyIng drawings.