How to Backwash Your Pool Filter?

How to Backwash your Pool Filter
Relaxing on a float, surrounded by crystal clear water is the goal of every pool owner. Unfortunately this “perfectly clean pool dream” can be a lot of work! Between treating your pool with chemicals, maintaining a healthy PH, skimming, vacuuming, and cleaning the filter, sometimes your place of relaxation can become quite the headache. Luckily, with the right technique and information, keeping your pool clean can be a breeze.

One of the most important aspects of maintaining your crystal clear pool is upkeeping the filter. Your pool’s filter circulates the pool water to remove small and large contaminants. You can think of your pool filter as a vacuum; it sucks in the water, removes any debris, and pushes clean water back into the pool.

Seeing the hard work your pool’s filter does, it becomes clear why maintaining your pool’s filter is crucial to the wellbeing of your outdoor oasis. Just like a vacuum, your pool’s filter can only suck in so much before needing to be emptied. In this article, I will explain how to clear the “gunk” out of your filter in the easiest and most hands-off way; backwashing.


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What is backwashing your pool filter?
I know, backwash typically refers to something gross, like little specks of food in a child’s drink. For the most part, unless you drop snacks in your pool, backwashing the filter should not involve any chewed up food!

Simply put, backwashing the filter is the process of the “gunk” clogging your filter coming out of the filter. In order to do this, you will reverse the direction of water flow in the filter to force the “gunk” out of the filter’s drain port.

I will go over why backwashing is important and provide easy to follow instructions on backwashing your pool filter; allowing your crystal clear pool to stay clean and ready for you to enjoy!

Why do I need to backwash my pool filter?
Backwashing your filter is important to extend your filter’s efficiency and life expectancy. Filters can be costly, but improper maintenance of your pool filter can lead to even more money drained from your wallet. By backwashing your pool filter, you are saving yourself time and money in the long run. While all filter’s eventually need to be replaced, backwashing allows you to use your filter longer before purchasing another.

Backwashing only applies to Sand and Diatomaceous Earth (D.E.) Filters (sorry, this article will not help cartridge filter owners). Sand and D.E. Filters remove contaminants from your pool by absorbing and trapping them inside of the filter. When these contaminants build up, your filter starts to work less efficiently. By backwashing the filter, your filter is freed of these contaminants and can work more efficiently again.

When do I need to backwash my pool filter?
The best way to determine when your pool’s filter needs to be backwashed is by monitoring the pressure gauge, which is measured in pounds per square inch (psi). When you install a new filter, record the PSI. As time passes, your filter will work to remove debris, which will result in an increase of PSI. While this increase in PSI ensures that your filter is working, it will also help you know that it is getting “gunked” up.

Once your pressure gauge shows a 10 PSI increase from when the filter was installed, you should backwash the filter to ensure efficiency.

What do I need to backwash my pool filter?
Something we all like to hear, all you need to backwash the filter is a backwash hose! No other chemicals or supplies are required, which means less time at the store and less money spent (woo!).

If you do wish to reduce the pressure on your filter, you can also purchase the Blue Torrent MyBot InGround Robotic Pool Cleaner. This Robotic Pool Cleaner is efficient, cost-friendly, and even comes with a lifetime warranty.

How do I refill a DE filter?
If you have a D.E. filter, you will want to replace some of the D.E. back into the filter after backwashing to ensure proper filter function.

The best way to do this is to combine the amount of D.E. Powder recommended by your pool fitler’s manufacturer with water. Once the proper amount of D.E Powder and water are combined, a sludge will form, apply this directly to the pool skimmer. Allow the pool filter to run at least eight hours to ensure the D.E. dispurses property into the filter.

During this process, do not swim in your pool to avoid D.E. exposure.

How do I backwash my pool filter with a Multiport Valve?
The steps below will walk you through how to backwash a pool filter with a multiport valve. REMEMBER: ALWAYS TURN OFF YOUR MULTIPORT VALVE POOL FILTER BEFORE BACKWASHING!

1. Turn OFF the pool filter system.
2. Connect the backwash hose to the filter’s waste port.
3. Turn the multiport valve to “Backwash”.
4. Turn the pool filter system ON. Let it run for 1-2 minutes (yes it is really this easy!!).
5. Turn the pool filter system back OFF. Turn the Multiport Valve to “Rinse”.
6. Turn the pool filter system ON. Let it run for 1-2 minutes.
7. Turn the pool filter system back OFF.
8. Return the Multiport Valve to “Filter”.

How do I backwash my pool filter with a Push-Pull Valve?
Backwashing the pool filter with a Push-Pull Valve is even simpler! Follow the steps below:
1. Turn OFF the pool filter system.
2. Connect the backwash hose to the filter’s backwash port.
3. Open the backwash gate,
4. Turn the pool filter system ON. Let it run for 3 minutes (yes it is really this easy!!).
5. Turn the pool filter system back OFF.
6. Close the push/pull valve.

Now, where do I put all of the “gunk”?
Congratulations! The “gunk” is removed from your filter…but where does it go now? Great question! The best option is to check your local city and state guidelines for waste disposal. As a helpful hint, storm drain and sewage drain disposal can lead to hefty fines, so I would not recommend this method.

As a guideline, most local governments recommend disposing of this waste into a sanitary sewer (not a storm drain or sewage drain) or a vegetated area on your own property. Again, check your local and state guidelines to avoid improper disposal and fines.

Backwash complete-now what?
You did it! What a great pool owner! Now that your filter is backwashed, your pool is ready to stay crystal clear and ready for your enjoyment.

By following these simple steps, you saved yourself time and money and learned a new skill to upkeep your pool!

Enjoy your clean pool- you earned it!

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