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WATER LEVELS - SALT - EQUIPMENT -  PLUMBING - POOL MAINTENANCE

How to Backwash my Pool for Clean and Clear Water...


When the multiport valve is set to filter, the water will flow from the pool, through the filter and then back into the pool again. The Sand (or glass) media acts to filter the debris, dirt and oil from returning to the pool. Backwashing reverses the flow of water through the sand filter, which dislodges this grime and dirt.


How to backwash a Pool

1.) Turn the pool pump off

2.) Open the waste line valve

3.) Turn the Multiport valve to point to the ' backwash' position

4.) Turn the pump back on and backwash for approx 2 minutes or until the water runs clear

5.) Check the flow window - Once the flow window is showing clear water Turn the pump off again

6.) Turn the Multiport valve to point to the ' rinse' position

7.) Turn the pump back on and rinse for 30 seconds

8.) Turn the pump off again

9.) Turn the Multiport valve back to the Filter position

10.) Close the Waste line valve

11.) Turn your pump back on again


NEVER : Turn your multiport valve whilst your pump is running



What does backwashing a pool mean?

A typical sand filter multiport valve has 6 different settings.

Filter - Backwash - Rinse - Circulate - Closed - Waste

When the multiport valve is set to filter, the water will flow from the pool, through the filter and then back into the pool again. The Sand (or glass) media acts to filter the debris, dirt and oil from returning to the pool. After a while though, it stands to reason that the sand (or glass) media becomes saturated with the dirt and contaminants and becomes clogged. Backwashing reverses the flow of water through the sand filter, which dislodges this grime and dirt. As you generally backwash to the waste line, you are ridding the swimming pool of this debris.

If left unchecked and if the filter becomes too clogged, it will not only lower the ability to filter the water, but it will also cause extra stress on your pool pump.


Why do I need to backwash my pool?

In simple terms : to Clear the filter, which filters the water.

The process of backwashing is aimed at dislodging trapped dirt and contaminants that are in the filter media by flushing them out through your waste line. Once the filter media is clean the water flow through your filter is increased and the back pressure on your pump is eased.


How often do I need to backwash my pool?

Of course, this would range depending on usage, the amount of surrounding debris, weather etc, but as a quick guide once a week would be ideal, but most pools should be done at least once a month.


Does my pool lose water when I backwash?

To backwash via the waste line is to run your pool water back through the filter, but rather than circulating the water back into the pool, it is flushed out through the waste line. Whilst the backwashing process is flushing out the dirt and debris, so is it flushing out your water with it. So backwashing a pool too often can mean that you lose a lot of water.


Quick tip : check that your timers are all still correct, to ensure that your pump will be running correctly


For more information, or if you need a little help, contact us 0432 105 352

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