How to Change the Filter Sand.

How to Change the Filter Sand step by step.

Having received the correct amount of filter media, the following procedure should be followed:-

• 1. Ensure the pool water is in good condition and at the right level. Make sure the skimmer and pump baskets are free from debris. Backwash the filter for 3 minutes then rinse for 20 seconds – Repeat procedure to so that the old media is as clean as possible, before you remove it.
• 2. Set EVERY valve to the closed position. Isolate from the mains supply, the circulation pump and all other on line electrical/gas appliances.
• 3. Remove filter drain plug cap, which is just above the filter base level. NOTE: Once the drain plug cap is removed, the water contained in the filter will be released. Ensure that any of the water will not damage surrounding equipment or decor. Use suitable drainage trays or hoses as required.
• 4. For filters fitted with the multiport valve at the side (side mount) remove the top lid, this will speed up the out flowing water from the drain plug.
• 5. Threaded lids can sometimes be difficult to unscrew. We suggest that you use a purpose made ‘Lacron’ lid tool (please email us if you would like to purchase one). Alternatively, it is possible to make your own tool from two 750mm lengths of 50 x 50 timber, each drilled with a 10mm diameter hole, 70mm from the end. Loosely join the two timber pieces using a 10mm nut and bolt to form an unequal cross. This can then be fitted over the filter lid and used to push against the fins to give far greater leverage. Do not hammer the lid, this will cause damage.
• 6. Having removed the lid of your filter, you will need to lift off the air bleed cap and rose distributor then remove distributor pipework. This can be disconnected by unscrewing the stainless steel cross head screw, which is situated inside the filter at 45° on the edge of the top bulkhead. Once the screw is removed the header pipe can be eased out of the bulkhead and carefully slipped off of the black – airbleed tube.
• 7. For filters fitted with a multiport valve at the top, the valve must be removed to gain access to the interior of the filter. Top mount filters have a central collector pipe unlike the side mount type.
• 8. Provided the media is free running a commercial type wet and dry vacuum cleaner can be used to suck out the old media. NOTE: You may need to use water from a hose pipe to help fluidise the media when vacuuming. Alternatively, it may be more appropriate to simply bail out the media using a plastic bowl approximately of 150mm diameter or smaller.
• 9. Whatever method of media removal chosen, particular care should be taken as you excavate around the lower underdrain pipework. This pipework can become brittle during years of service and any damage that may occur could result in sand being passed back to the pool once the filter is re-commissioned. It may help to wash around the underdrain pipework with a garden hose to assist with removing ALL the old media.
• 10. Once the filter is completely empty of old media, it is advisable to fill the filter with water by about one third of the tank depth. This water will break the fall of the fresh media, reducing its impact on the underdrain pipework. Cover the end of the airbleed tube with adhesive tape or similar to prevent sand blocking the pipe bore.
• 11. Make sure that the NEW fresh media is dry and free running. Open the sacks carefully to avoid wastage and to assist in making the flow more controllable. Pour the media in slowly, and continue until half of the required amount is in place. At which point you should push the media around inside the filter making the surface roughly level.
• 12. Pour the remainder of the media in, but keep a careful check on the media height level. On most residential filters, the correct height is about 30 -50mm above the centre of the filter. This level may be higher on commercial filters – refer to filter technical specifications. NEVER FILL THE FILTER COMPLETELY WITH MEDIA!
• 13. Once the correct amount of media is in the filter, again push the surface layer around until roughly level. Then clean the lid area, paying particular attention to the threads which must be completely free of any media or dirt etc.
• 14. Remove the tape from the airbleed tube and clean and refit the distributor pipework, rose and airbleed cap. Thoroughly clean the lid and ‘o’ ring. Check to ensure that all dirt and grit is removed by screwing the lid into the filter. If dirt is still present you will hear a grating sound.Once you are sure that the lid and threads are totally clean you can then apply a liberal amount of Vaseline to the lid threads and ‘o’ ring. Then refit the lid hand tight only!
• 15. Open appropriate valves and reset to BACKWASH. Re-activate the main circulating pump. BACKWASH for at least 3 minutes. You will notice that the backwash water contains a colour stain – this is normal but must be completely clear before filtering can start. Stop the system then rinse for 1 minute. Stop the system and manually re-tighten the lid by another one-third turn. Then do a further backwash and rinse until the out flowing water is completely clean.
• 16. Re-set the valve to filter position, switch the pump on and observe the water flowing back to the pool, which should be noticeably, more vigorous. Once you are satisfied that the filter is running correctly you should re-set all other on line equipment, re-setting or adjusting timers etc.

Kirsty Edwards (Sales Manager)

This entry was posted on Thursday, April 17th, 2008 at 1:55 pm and is filed under Installation Info. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.