How Do You Backwash A Pool?

If you are the proud owner of a swimming pool, then you probably will have heard of backwashing it.

This is a common part of swimming pool maintenance, and something that is very important to do if you want your swimming pool to continue operating well. 

How do you backwash a pool

Backwashing is great because it cleans the filter of your swimming pool, ensuring that it does not become flooded with dirt and germs. But, if you are new to owning a swimming pool, you might be unsure what backwashing is. 

In this guide, we’ll be taking a detailed look at backwashing your swimming pool. From what it is, to why we do it, to how to do it.

There is so much that you need to know about this technique if you own a swimming pool. So with no further ado, let’s get started.

What is ‘backwashing’ a pool?

If you are reading this, and are new to owning a swimming pool, then you might be completely confused as to what ‘backwashing’ is.

The term doesn’t sound all that pleasant, but it is actually pretty self-explanatory what this consists of.

As it suggests, backwashing involves washing the filter of your swimming pool by reversing the flow of water through the filter.

 Cleaning equipment that is added to the water in the pool then passes back through the filter, cleaning it and dislodging any dirt, dust, or debris. 

When you own a swimming pool, it is easy to get into a routine of cleaning the water in the pool itself. It is also easy to know when to clean your swimming pool water because it will become visibly dirty.

But hidden parts of the swimming pool, such as the filter, can be difficult to know when to clean. This is why it is best to get into a routine when cleaning the different parts of your swimming pool.

Backwashing your swimming pool will clean the filter and flush the dirt out through the multiport valve waste line, leaving your pool clean. So, it is important that you do this regularly. 

Why do you backwash a pool?

You might be wondering why you need to backwash your pool. After all, you regularly clean the water, so surely that is enough to keep the pool clean, right?

How Do You Backwash A Pool?

Wrong! Even though cleaning the water in your swimming pool is very important, there are lots of other things that you need to do to upkeep the maintenance of your swimming pool. 

Backwashing is just one of them. Swimming pools are great, but they are also a lot of work, so it is important that you bear this in mind when you consider installing one. 

Swimming pools are hard work because they require very delicate chemical balances in order for them to operate properly.

The filter in your swimming pool plays an incredibly important part in maintaining this chemical balance, which is why it mustn’t become clogged with dirt.

If it does become clogged, then your swimming pool will not remain clean, and it will become unsafe to use it. Thankfully, cleaning your filter is very easy because you can simply backwash it by reversing the flow of water.

We have made this sound like it is very easy to do, but let’s take a look at exactly what you need to do to backwash your pool. 

How to backwash a pool

We have spent a lot of time talking about backwashing your pool, now let’s take a look at exactly how to do this.

All swimming pools are different, but generally speaking they all operate in the same way when it comes to backwashing. To backwash your pool, follow this step-by-step guide. 

Step One

First things first, it is incredibly important that you switch off your pool pump. This is incredibly important to ensure that you do not put yourself at risk. So, once you have done this, double check that it is off before you go any further. 

Step Two

Focus on your filter valve. If you take a look at the handle of your filter valve, you will find that it has a ‘backwash’ position. When you find this, simply turn the handle in this direction and ensure that it locks in place. 

Step Three

Turn on the pump. Now that your filter is in backwash, when you turn on the pump, this will activate the backwash function.

Let this run for around 2 minutes, or until the water that is in the sight glass of the filter runs clear. When it does, turn off the pump. 

Step Four

Focus back on your filter valve. Look for the ‘rinse’ position on the valve and rotate it until it is in this setting. Once again, ensure that the handle locks into place before you go any further. 

Step Five

Once again, switch on the pump and let it run for a minute. If after a minute the water in the pump is not clear, leave it to run until it is. When it clears, turn off the pump. 

Step Six

Look at your filter valve once more. It is now time to set the filter valve back to the original setting, so look for ‘filter’ on the handle.

Rotate to this setting and ensure that it is locked in place. When it has, it is time to switch the pump back on, you can then leave it to run. Your pool has now been backwashed and is ready to use. 


In short, backwashing your swimming pool isn’t as difficult as you might expect it to be.

As its name suggests, backwashing simply consists of you adjusting the filter on your pool so that it pumps water backward through the filter rather than into the pool. 

Ideally, you should backwash your swimming pool around once a week if you want to keep on top of the maintenance. This is an easy part of pool maintenance to forget, so it is very important that you build your maintenance routine around it.