TAUNUS SAND FILTER OWNER'S MANUAL REV.01

Transcription

1 TUNUS SND FILTER OWNER'S MNUL REV.01

2 Index 1. FILTER DESIGN STNDRDS CONSTRUCTION CHRCTERISTICS CCORDING DIN EQUIPMENT DOUBLE WELDING CONNECTIONS GENERL DIMENSIONS MEDI RECOMMENDTIONS CHEMICL RESISTNCE HNDLING ND CUTIONS FILTER PCKGING FILTER STOCKGE HOW TO MOVE YOUR FILTER IN THE FCILITY Use a froklift Use the eyebolts Never roll the filter Never drag the filter Do not use hooks Long filters void knocks CHOOSING THE RIGHT EMPLCEMENT FOR THE VESSEL Flat floor Enough space INSTLLING THE FILTER Install the manifold Test first with water FILLING THE FILTER Check the internals Use a water bed Start with a backwash RECOMMENDTIONS FOR THE PRESSURE VESSEL OPERTION Use pressure gauges Watch the operating pressure Check the pressure difference Perform a backwash if required Beware of corrosive substances! FILTER MINTENCE Just clean with water UV protection IMPORTNT RECOMMENDTIONS TO TKE INTO CCOUNT OPERTION MNUL CHECK THE PCKGING GENERL SPECIFICTIONS IDENTIFICTION OF COMPONENTS INSTLLTION SPECIFICTIONS INSTLLTION INSTLLTION OF THE PRESSURE GUGES INSTLLTION OF THE BTTERY SUPPORT STRTING UP NORML WORKING CYCLE FILTRTION BCKWSH BCKWSH WITH IR ND WTER (ONLY FOR FILTERS WITH NOZZLE PLTES OR DOUBLE LTERLS) RINSING DRIN CLOSED VLVE BTTERIES. POSITION OF THEM IN ECH OPERTION Batteries with 4 valves Batteries with 5 valves DRINING THE SND FROM THE FILTER OTHER RECOMMENDTIONS MINTENNCE TBLE HED LOSS FROM SND FILTERS WITH VLVE BTTERIES SFETY WRNINGS POSSIBLE FULTS DO ND DO NOT i

3 5. GURNTEE CERTIFICTE SND FILTER MODEL TUNUS GENERL TERMS INDIVIDUL TERMS LIMITTIONS CERTIFICTES DECLRTION OF CONFORMITY 97/23/EC ISO CERTIFICTE LVHT SPRE PRTS ii

4 1. FILTER 1.1. Design standards ccording to the European Directive for Pressure Vessels 97/23/CE, it is established in its article 3, section 3 that the pressure vessels with inferior or equal characteristics to the values specified in chapters 1.1, 1.2, 1.3 and in section 2, have to be designed and manufactured according to the standard procedures in order to ensure a safe use. t the same time this equipment will be supplied with an instruction manual and will be labeled specifying the manufacturer, these equipment do no have to be CE labeled. ll the equipment specified are manufactured under the standards specified in its article 3, section 3, since they are equipment with a maximum working pressure of 2,5 bar, maximum working temperature of 40ºC and not adequate to contain dangerous liquids. See chemical resistance chart. In order to design the pressure vessels, three world recognized standards have been taken into consideration; D-Merkblatt N1 (Germany), BS4994 (United Kingdom). These standards specify the calculation method of the vessel, the raw materials requisites, and the essays to be performed to the materials, prototypes and products. The vessel calculations are based on the standards mentioned previously, choosing in each circumstance the mathematical model that is more adequate to our productive process and also considering the characteristics of the materials used. Each pressure vessel with no exception, once it is finished and before expedition, is submitted to a hydraulic pressure tests of 1 1/2 times the maximum working pressure. The conditions for the product acceptance require there is absolutely no leak at all in any part of the vessel. Once the pressure essay is passed, our quality inspectors verify the accomplishment of all the technical specifications of the product Construction Characteristics according DIN (1) Smooth surface non-reinforced internal layer, in contact with the filtered media in vinylester material. CSS-PH. (2) Non-oriented layers, with high vinylester resin content 65% CSS-PH-M. (3) On the heads, connections and manholes: oriented layers low vinylester resin content 45% CSS-PH-MW2. (4) Non-oriented layers with high vinylester resin content 65% CSS-PH-M. (5) Oriented wounded layers with circumferential fibers and high mass content 70% with vinylester CSS-PH-FM6. (6) Oriented wouded layers with longitudinal fibers and high mass content 70% with vinylester CSS-PH-FM6. (7) Oriented layers with circumferential fibers and high fiber mass 70% with vinylester CSS-PH-FM6. (8) External protective coating light grey colour min. 400 microns. (1) (2) (3) (4) (5) (6) (7) (8) Mechanical filtration by means of single layer or sand and antracite multilayer bed, only for use in swimming pools. Maximum pressure 2,5 bar. Maximum temp. 40ºC 1

5 1.3. Equipment Top air relief at the highest point DN 400 mm. top lid with elevation rings Bobbin wound vessel completely in vinylester and E glass fiber Dirty water inlet with double welding reinforced with PVC inside DN 400 mm or 500 mm or 600 mm according choosen model side manhole Clean water outlet with double welding reinforced and PVC inside GRP base GRP Flange air backwashing conection and inspectioun under nozle plate Double welding connections This connection design ensuring high performance. These have been welded to the vessel either in the inside and the outside PVC pipe Internal welded Bobbin wound vessel External welded DIN Flange with PVC inside 2

6 1.5. General dimensions D=1050 to D=1400mm OD O400 OG2 150 OJ 500 OK B H L /4" OK NOZZLES 0,5 mm OG1 C T OP ø D (mm) ø E (mm) (m 3 /h/m 2 ) ø K (mm) H (mm) (liters) (kg) (kg) (m 3 /h) (m 2 ) (einheiten) B C ø internal diameter ø external diameter Recommend filtration velocity Inlet/outlet connections Total height Volume L ø P (mm) T Underdrain acces hole ø J ø G1 ø G2 ø I (mm) ø O (mm) ø R (mm) m/h Service weight Net weight Recommend flow Surface filtration Number of nozzles Base Backwash air inlet ir relief outlet Top manhole Lateral manhole Shightglass Recommended backwash velocity , , ,

7 D=1600 to D=2350mm OD OG2 O400 OJ OK B 1200 H L N 3/4" OK NOZZLES 0,5 mm OG1 C T OP ø internal diameter ø external diameter Recommend filtration velocity Inlet/outlet connections Total height Volume ø D (mm) ø E (mm) (m 3 /h/m 2 ) ø K (mm) H (mm) (liters) (kg) (kg) (m 3 /h) (m 2 ) (einheiten) B C L ø P (mm) T N Underdrain acces hole ø J ø G1 ø G2 ø I (mm) ø O (mm) ø R (mm) m/h Service weight Net weight Recommend flow Surface filtration Number of nozzles Base Backwash air inlet ir relief outlet Top manhole Lateral manhole Shightglass Recommended backwash velocity , , , ,

8 1.6. Media recommendations Ø internal diameter (mm) Height (mm) SINGLE LYER Sand 0,4-0,8 mm (kg) Gravel 1-2 mm (kg) MULTI LYER Hidroantracite (kg) Sand 0,4-0,8 mm (kg) Gravel 1-2 mm (kg) Gravel 3-5 mm (kg) Chemical resistance Chemical name Chemical formula Concentration max.temperature ºC cetic cid CH 3 COOH 5% 20 R luminium Chloride lcl 3 Saturated solution 40 R luminium Hydroxide l(oh 3 ) Solid suspension 40 R luminium Sulfate l 2 (SO 4 ) 3 Saturated solution 40 R Boris cid H 3 BO 3 5% 20 R Ferric Chloride FeCl 3 Saturated solution 40 R Ferric Sulfate Fe 2 (SO 4 )3 Saturated solution 40 R Ferrous Sulfate FeSO 4 Saturated solution 20 R Hydrochloric cid HCl 5% 20 R Lead acetate Pb(C 2 H 3 O 2 ) 2 3H 2 O Saturated solution 40 R Nitric cid HNO 3 5% 20 R Ozone mixed in water O 3 0,4 ppm 40 R Phosphoric cid H 3 PO 4 5% 20 R Salt Water - Sea water 40 R Sodium Carbonate Na 2 CO 3 Saturated solution 40 R Sodium Hydroxide NaOH 5% 20 R Swimming pool water R *The concentrations, unless it is said the opposite, are expressed like percentage in mass to 20ºC. R: resistant 5

9 2. HNDLING ND CUTIONS PLESE RED THIS INSTRUCTIONS CREFULLY In order to avoid any vessel damage or a future malfunction of the filter due to an inadequate handling and operation Filter packaging Servaqua filters are supplied properly packaged on wooden pallets adequate to the size of the filter. They are usually supplied in an upright position unless the filter height is above the standards. Then the filter is packed horizontally, in an special pallet for this purpose, and is fixed to the pallet using nylon slings 2.2. Filter stockage If you are not going to install the filter strait away, it is preferably to keep it with its original packaging. way from sun and avoiding extreme temperature. Max. temp. stockage 50ºC Min. temp. stockage -5ºC 2.3. How to move your filter in the facility Use a froklift lways use a forklift or a crane to download or upload a filter from the truck, and if possible, to take the filter to its final position in the facility where it is going to be operating. 6

10 Use the eyebolts If this was not possible, the eyebolts of the filter should be used: WRNING: The eyebolts should only be used when the filter is empty of sand. Filters are supplied with eyebolts (elevation rings), use them to lift the filter and carry it to the desired place with the help of a crane or a forklift: Use eider a nylon reinforced sling or a steel cable. WRNING: Check the Net Weight of the vessel with the supplier in order to choose the right strength of sling Never roll the filter To transport them; connections and lateral manholes could get damaged Never drag the filter Even with the help of slings, this could seriously damage the base of the filter. Never drag the filter through the inlet and outlet connections. 7

11 2.3.5.Do not use hooks Inside of the pressure vessel, to lift it or drag it Long filters When a vertical vessel is delivered in an horizontal position due to its height, it is recommended to place the filter in a vertical position using the elevation rings. This should always be performed with the filter in its original packaging and wooden skid void knocks void knocking the filter to the floor, walls or anywhere that could damage the filter. lthough the filter resists internal pressures, the external structure of the filter is very vulnerable to external knocks 8

12 2.4. Choosing the right emplacement for the vessel Flat floor Make sure that the floor surface is perfectly flat: n uneven surface could debilitate some parts of the filter structure while operating Enough space Make sure that there is enough space around the filter to allow for any maintenance work Installing the filter Install the manifold Once the filter has been placed on the final position, check that it is in good condition. Prior filling the filter with the media, install the manifold using the right gaskets to seal the connections and always using the manifold supports. The manifold support will take all the weight of the valves and water, reducing the stress on the connections. lways use plastic connections. The water tightness is given by gasket or o-ring, so please; do not tighten too much the bolts. Please note that fiberglass reinforced vessels expand when they are submitted to internal pressures. This should be taken into account when connecting the vessel to the facility Test first with water It is necessary to test the system with water at the normal working pressure, in order to check for any problem before filling the filter with the filtration media. 9

13 2.6. Filling the filter Check the internals Make sure that you have checked all the internals of the filter. The distributor and the collector system must be in good condition. Make sure that all the nozzles or the laterals of the collector system are in place and tight enough Use a water bed Before filling the vessel with the media, fill the filter with water up to half the height. This will prevent the collector system from getting damaged. Take into consideration the slot size of the collector system, in order to use the right filtration media. This media should be larger than the slot size of the nozzle or laterals, 0.2, 0.3 or 0.5 mm (check with your supplier in case of doubt) In sand filters, start filling with sand gravel that will cover the nozzles or laterals, doing this carefully, so the collector system does not get damaged. This first layer should cover 10 cm above the collector system. Sand should be distributed evenly over the whole surface area. Introduce the next layers in the filter following the same procedure. Clean carefully the filter neck in order to remove any residue and check that the o-ring of the lid is placed in the right position Start with a backwash In sand filters, once the filter is filled with sand, perform a backwash in order to get rid of any dust and impurities of the sand. Perform this operations according to what is indicated in the operations section. 10

14 2.7. Recommendations for the pressure vessel operation Use pressure gauges Install pressure gauges at the inlet and outlet of the vessel in order to control the operating pressures. The pressure vessel that you bought, has been designed to operate at a specific pressure. The working pressure of the filter should never exceed the maximum working pressure the filter has been rated with Watch the operating pressure Pressure vessels do not support negative internal pressure, therefore adequate measures should be taken in the facility in order to avoid this situation. It is important to design the facility in order to maintain a minimum pressure stability, this means trying to avoid continuous or unnecessary pressure variations in the filter, since this could lead to causing fatigue in the filter and a premature ageing. In this case the guarantee could not be acceptable by the manufacturer. When choosing an automatic valve system, make sure that the operation of the valves is slow enough, in order to avoid any sudden drop or increase in pressure. ny circumstance that could cause a hammer stroke should be avoided, use all the necessary security systems to avoid them Check the pressure difference The difference in pressure in the filter between the inlet and outlet should never exceed 0,8 bar. This could cause a breakage of the nozzle plate or the laterals collector system Perform a backwash if required void the clogging of the filtration media, and perform a backwash whenever it is necessary. The backwash should be performed using the adequate water flow at a low pressure, never above the maximum operating pressure of the filter: When using air to perform a backwash, use the adequate air flow (recommended rates of 60 m3/h/m2). Never use a compressor, since this could severely damage the filter. Use a blower, ensuring that the internal pressure of the filter when backwashing does not exceed 1 bar. Make sure that here is an air vent open when backwashing with air. Check regularly the state of the filtration media. Some fluids may contain substances that can obstruct the collector system over time. Check the state of the collector system when performing a change of the filtration media or a periodical revision. 11

15 2.7.5.Beware of corrosive substances! The use of any corrosive substance ( high concentrations of ozone, or other oxidants, highly concentrated acidic or basic solutions ) could severely damage the internal structure of the filter. Check with your supplier before using any corrosive substance inside the filter Filter maintenace Just clean with water The filter could be washed regularly in order to avoid the accumulation of dust and impurities on the vessel surface. The washing should be done only with water. void the use of detergents that could damage the filter surface UV protection In case of having a bobbin wound filter installed outdoors, it should be painted regularly in order to prevent damages caused by UV radiation. Use the adequate UV protective paint. 12

16 2.9. Important recommendations to take into account 1. The pressures stated in this catalogue correspond to the maximum working pressures. It is recommended to choose the equipment so the maximum working pressure is 20% higher than the maximum pressure that can be achieved by the pumping group. 2. The equipment in this catalogue has been submitted to fatigue tests up to cycles, as stated previously. It is important to design the facility in order to maintain a minimum pressure stability, this means trying to avoid continuous or unnecessary pressure variations. ny change in the internal pressure of the filter, even the small ones, generate a working cycle. The accumulations of an excessive number of work cycles in one day lead to a premature ageing of the equipment due to fatigue. 3. On the equipment with nozzle plates, the differential pressure created between the two chambers can not exceed in any case 0,8 bar of the maximum working pressure of the filter in order to avoid a possible plate breakage. 4. For the filter backwash with air, the pumping group chosen should never exceed 0,8 bar of pressure inside the vessel. 5. Negative pressures should always be avoided inside the vessel, since these have only been designed in order to resist positive internal pressures. 6. When installing the filter, think of the necessary free space, in order to perform a correct maintenance, or the filter replacement if necessary. 7. This pressure vessel must be installed in such a way that the recurrent work and tests are accessible and the type plate is easily legible. The operation of the filter boiler and its equipment must be possible under safe conditions. 8. This pressure vessel and their equipment must be protected against mechanical influence from outside to prevent damage with dangerous consequences for operators or third parties and for property. 9. Filter boilers must be mounted in such a way that gases, vapours or liquids leaking from safety devices can be diverted without danger. 10. In the operating state and when the filter operation is stopped, the plant must be protected from frost. 11.During shutdown in winter, the filter boiler must be totally emptied of liquid. Drain cocks must be installed by the customer. 12.Check filters for transport damage and ensure that connections and manholes are correct and filter nozzles are tight 13.Test pressure vessel before load the sand, the maximum pressure of theist mustn t overcome the maximum working pressure. The first pebble and sand layers must be filled and distributed uniformly via the manhole. 14.In the process note that the rough filter material forms the lowermost layer and the fine material the uppermost layer. In multilayer filter boilers, the uppermost filter layer is hydroanthracite. 15.nthracite must be soaked in water sufficiently long before commissioning and before first backwash (approx. 24 hours). The first backwash continues until the rinsing water is clean. 16.The owner must provide instructions, particularly about commissioning and shutdown, maintenance, behaviour in the event of extraordinary incidents, troubleshooting (operating instructions). Operating manuals must be made available. The operating manual must be accessible at any time by the operating personnel 17.Pressure containers must only be operated by trained persons who are expected to carry out their tasks reliably. Trained persons are those who have been instructed in the tasks assigned to them and in the possible dangers in case of improper behaviour and have been trained to handle such dangers. 13

17 3. OPERTION MNUL IMPORTNT: The instruction manual that you have in your hands contains fundamental information on the necessary security measures which need to be adhered to when installing and commissioning the filter. It is therefore essential that both the installation engineer and the end user read these instructions before proceeding any further. "In order to archive optimum performance from your filter, please see the following instructions" Check the packaging Check that the filter and all its components are in good condition after transportation. There is a box with the filter, which contains pressure gauges, along with other accessories. There will also be a guarantee and test certificate General specifications Filters are the most important part of a water filtration system, and their function is to remove suspended solids and clarify the water. The effect of correct filtration will influence the results of disinfectant process. The principle of filtration involves retaining the suspended particles that the water tries to carry with it through the filter sand bed. The water treatment process involves a range of equipment besides filters, such as; pumps, chemical dosing, pool shell fittings, which ensure the correct suction and return of water, which with the rest of the equipment ensures the correct circulation and maintenance of the water quality. Whilst standards are approaching homologation throughout Europe, each country normally has its own standards, regulations or recommendations governing private and public pools, and installers should adhere to these when designing and installing any system. ll designs and all materials used must meet the relevant standards. The filtration quality may depend on different factors: Design of the filter, type of collector used - collectors or nozzles, media bed depth, specifications and density of the filtering material etc. t the same time the filtration velocity is a determining factor when seeking good quality filtration and a velocity of no more than 40 m/h is recommended. Bobbin filters are manufactured from polyester resin and glass fibre materials, which have excellent anticorrosive properties. The interior includes a collector and diffuser made from PVC and PP plastic. They are also resistant to salt water and can operate up to a maximum temperature of 50ºC. The special layer of isopthalic resin on the interior of the filter gives it maximum durability against wear and tear and abrasion, also enabling it to be used with potable water. Filters may also be manufactured on request with a vinylester lining, which is resistant to most chemicals including ozone. 14

18 3.3. Identification of components ) Filters with laterals (FIG.1) 1. Lid for addition of media, and inspection. 2. ir relief connection 3. Pressure gauge 4. Sight glass (optional, on request) 5. Reinforced polyester and fibre glass tank 6. Dirty water inlet 7. Clean water outlet 8. Water collected via laterals 9. Reinforced polyester and fibre glass base 10. Manual water drainage 11. Sand discharge cap 12. Side man hole (optional, on request) 13. Filtration media 14. Water diffuser system 15. Eyebolt to transport the filter (only for use when the filter is empty) (FIG.1) B) Filters with nozzle plates (FIG.2) 1. Lid for addition of media, and inspection. 2. ir relief connection 3. Pressure gauge 4. Sight glass (optional, on request) 5. Reinforced polyester and fibre glass tank 6. Dirty water inlet 7. Clean water outlet 8. Water collected via nozzle plate 9. Reinforced polyester and fibre glass base 10. Manual water drainage 11. ir inlet connection for backwash 12. Side man hole and sand discharge 13. Filtration media 14. Water diffuser system 15. Eyebolt to transport the filter (only for use when filter is empty) (FIG.2) 3.4. Installation specifications In order to achieve successful installation it is important to consider the following points: Choose a pump suitable for the required flow at 10m head (water). In order to backwash the filter, the system of pumps and filters must combine to obtain the necessary flow, which can be from 40-50m/h lateral models, and up to 60m/h for nozzle plate models. To scour the filter with air (nozzle plate models or models with double laterals) it will use one or more air blower or capable of supplying air at a velocity of 60m/h 300mbar. Never use a compressor because damage could occur due to excessive pressure. It is advised to install the filters below the level of, and as close to the pool as possible. The plant room where the filters are installed should be well ventilated and have the necessary drainage channels available to allow escape of water, should a pipe, filter or pump leak in the case of an accident, preventing damage to any equipment. If it is no possible to install such drainage measures then an alternative automated system (e.g. submersible pumps) should be installed for water removal. 15

19 3.5. Installation Filters are delivered packaged and palleted, due to their weight and volume. This can make them difficult to manoeuvre around the building site and install so it is recommended that they be transported by fork lift, crane, etc. Filters are made of plastic, and although they are designed to be resist to internal pressure, they can be susceptible to external damage. It is important to ensure that the filter does no receive any external knocks during installation or operation that could damage the base, the tank or any connections. lways use suitable plastic connections and make ensure they are fitted with suitable supports and are not forced, or under stress. Filters like other items of plant, will need regular checks, so it is essential to leave a suitable working clearance above and around the filter. (FIG. 3) Correct installation of the filters: Place the filters in their designated position, and ensure that they are stable and the floor is perfectly flat. (FIG. 4) ssemble the batteries on the filters, ensuring they are not stressed. Remember that the water tightness of the unions is achieved with seals and gaskets, so do not over tighten the bolts. Do not use Teflon (PTFE) tape. Install adequate battery/pipe supports and adjust their height accordingly. Plumb the batteries to the pump discharge pipes, the return pipes to the pool and to the waste drain Installation of the pressure gauges Once you have installed the pressure gauge panel on the flange of the filter connection, note the flexible plastic and transparent pipes that must be connected between the pressure gauges and the ¼ threaded holes in the battery tees, as the illustration shows (FIG 5). The pressure gauge panel clearly identifies the pressure gauge that controls the inlet and outlet pressures. The pressure gauges indicate when backwash of the filter is necessary. For example, in a clean filter the entrance pressure should be between 0.8 and 1 kg/cm2 and the exit pressure should be between 0.4 and 0.6 kg/cm 2. When the difference between the pressure in the inlet pressure gauge and that in the outlet pressure gauge is 0.8 kg/cm 2 or higher, then it is time to backwash the filter. 16 FIG.3

20 FIG.4 FIG Installation of the battery support Once the battery has been installed it is recommended to set up special supports in order to hold the battery s weight as well as the weight of the water that flows through it. It is recommended to install adjustable height supports: To install them it is first necessary to adjust the height of the clamps according to the battery and then fix the support to the floor with the expanding bolt provided. 17

21 3.8. Starting up Remove the lid of the filter trying not to damage the joints or the surrounding area around the lid. Check that all the filter components are in good condition and ensure that the laterals or nozzle plate are secure, as they may have come loose or been damaged in transit. Fill the filter approximately half full of water. Introduce the sand, ensuring you first pour in a support layer, enough to cover the groove of the laterals or nozzle plate, covering them by approx. 10cm. This should be done very carefully so as not to damage any internal components. Whilst filling the filter with sand ensure that you distribute the sand evenly over the whole surface area. Introduce the desired sand size, up to the maximum filtration height limit. Carefully clean the filter neck, the seal and the lid before proceeding with the assembly. It is also advised to grease the screws before putting in the nuts, and once the lid assembly is complete, put the flanges (supplied with the filter) to the screws. Close the filter placing the seal in its correct position. Once the filter is full and properly closed, it is necessary to backwash the filter. To do this follow the instructions in the section labelled backwash Normal working cycle FIG.6 18

22 3.10. Filtration With the pump stopped set the valves to the position labelled filtration. During the filter s normal operation, it is recommended to periodically check the entrance and exit pressure gauges and carry out a backwash when the difference in pressure is equal to or more than 0.8 kg/cm 2. In industrial applications the pressure difference should not exceed kg/cm 2. Normally when referring to filtration for pools the entrance pressure gauge shows a pressure of 0.8-1kg/cm 2 and the exit pressure gauge kg/cm 2 (standard pressure when the filter is clean). FIG.7 s the filter gets dirty during its use, the entrance pressure gauge experiences an increase in pressure at the same time as the exit pressure gauge shows a fall in working pressure. EXMPLE Entrance pressure gauge 1.4 kg/cm 2 Exit pressure gauge 0.6 kg/cm 2 Pressure difference 0.8 kg/cm 2 In this case it is necessary to backwash the filter Backwash FIG.8 The bed of sand inside the filter forms thousands of channels through which the water flows and logically they collect impurities and solid deposits that the water brings with it to the filter. In time these deposits block the channels and it is periodically necessary to clean the filter to leave it in optimum working condition and drain the dirt that had collected. It is recommended to follow DIN and DIN for backwash in filters manufactured according these DIN standards. To carry out a backwash cycle, LWYS WITH THE PUMP SWITCHED OFF, set the valves to the backwash position indicated on the template. 19