Backwashing your Swimming Pool Filter

After a while the situation arises when the filter becomes overloaded with trapped material and needs to be “BACKWASHED”, this point is indicated when the reading on the pressure gauge fitted to the multiport valve or filter tank rises by a maximum of 4 p.s.i. or 0.25 bar above the clean running pressure. However, regardless of pressure, the filter should be backwashed at least once every ten days.

The backwash sequence of operations is as follows:

1. Ideally ensure that the pool water level is approximately 25mm above the centre-line of the surface skimmer opening, as you will be disposing of pool water to waste in the process of backwashing.

2. Switch off pump, set multiport valve handle to “BACKWASH”, switch on pump and allow to run for 2 minutes. If you are fortunate enough to have a filter with a clear plastic lid in the top, then instead of timing your backwash you can observe the flow of water and go to the next stage when the water runs clear.

3. After 2 minutes or when the water runs clear, switch off pump, set multiport valve handle to “RINSE”, switch on pump and run for 10 seconds minimum.

4. After 10 seconds, switch off pump, set multiport valve handle to “FILTER”, and switch on pump.

The backwash should now be complete and the pressure gauge reading should have dropped back to the clean running pressure which you noted when first starting up your filtration equipment from new.

Always remember to top up the pool level after every backwash.