How to Backwash Your Pool Filter – The Right Way

backwashing pool filter

Do you just install a new pool in your home and you do not know how to backwash your pool filter? Don’t be stressed out. It is not as complicated as it looks.

There are some techniques to follow. Plus, you should remember when to backwash the filters.

It is necessary to learn how to clean the filter because it enhances the longevity of the pools. If you are looking for a service related to pool renovations in Delaware, you are at the right place. Check our website and hire our professional to do the job.

This guide will ensure step-by-step guidance on backwashing of the filter.

We have also extracted some of the tips to execute the procedure efficiently. So let’s discuss it without wasting your valuable time.

What is a Backwashing Pool Filter?

Backwashing is the technique of cleaning your filter system by reversing the flow of water. Pool filters remove organic waste by channeling water through a porous substance, such as sand.

However, even as they return clean water to the pool, the filter will accumulate progressively larger particles over time.

The accumulation of undesired particles frequently leads to increased pressure on the filter, diminishing its performance and potentially causing damage. Backwashing a pool removes contaminants and debris, pushing them into a hose via the pool pump or waste line.

How to Backwash Pool Filter?

Backwashing is an integral part of pool maintenance, especially for sand and D.E. (diatomaceous earth) filters. It’s a process that cleans and resets the filter so it can continue to remove particles from the water effectively. Here’s a step-by-step guide on how to backwash your pool filter:

Turn Off the Pool Pump

Before starting the backwash sand filter process, turn off the pool pump to prevent damage to the system.

Turn the Valve to Backwash Mode

For most pool filters, there will be a multiport valve or a push-pull valve that controls the flow of water. Turn this valve to the “Backwash” or “Backwash and Rinse” position.

Turn On the Pump

Once the valve is set to “Backwash,” turn the pool pump back on. The pump will start pushing water backward through the filter, dislodging and expelling any trapped debris.

Watch the Sight Glass

If your filter has a sight glass, you will see the water coming out initially as dirty. Let the backwash pool run until the water in the sight glass is clear or until the manufacturer’s recommended backwash time is reached (usually about 2-3 minutes).

Stop the Pump and Rinse

After backwashing, turn off the pump and set the valve to the “Rinse” position. Turn the pump back on for about 30 seconds to flush out any remaining debris.

Return to Normal Operation

Turn off the pump, set the valve back to its normal “Filter” position, and turn the pump back on. Your pool filter is ready to continue filtering the water. It also helps in pool bottom cleaning when you winterize the pool.

Check Pressure

It’s a good idea to check the filter pressure gauge before and after backwashing. A significant drop in pressure usually indicates that the backwash was effective. It is an essential part of how to backwash a pool filter.

Monitor Water Chemistry

After backwashing, it’s common for the water chemistry to be temporarily affected. Check your pool water and adjust the pH and chlorine levels as needed.

Remember that appropriate and regular pool filter maintenance is important for keeping the water clean and safe for swimming. Always consult your filter’s manual for specific instructions and guidelines tailored to your specific filter model.

How Often is Required to Backwashing Pool Filter?

One of the most common queries is, “How often should you backwash a pool.” When and how often you backwash your pool is determined by the sort of filtration system you employ and how frequently you use it.

If your pool is surrounded by trees and shrubs, you will also need to call a backwash pool expert more frequently.

The amount of debris or dirt will determine the time required to backwash your pool in the filtration system. A good rule of thumb is to backwash the filter when the pressure gauge shows a 25-30% increase over the clean pressure.

Your weekly pool maintenance checklist and plan will tell you how often to backwash a pool, but ideally, you should do it once a week. If you’re still wondering how often to backwash pool filters, look into the industry recommendations.

Typically, you should backwash a pool if the pressure on your filter reads 8-10 PSI at the start. So, to answer the question of how often to backwash your pool, check the PSI. If the filter performs properly at 16 PSI and then increases to 25 PSI, your pool needs a backwash.

When Not to Backwash Sand Filter

There are a few scenarios when it’s best not to backwash a sand filter. The first is when the filter hasn’t reached its maximum pressure threshold or when the filter pressure is only slightly elevated.

Backwashing too frequently can actually be detrimental to the filter’s efficiency by prematurely removing the beneficial microbial layer, known as the biofilm. Which assists in trapping and breaking down dirt.

Another scenario is when you’ve recently added pool chemicals, such as shock or algaecide, that require some time to circulate and be absorbed by the water before backwashing.

Lastly, if the pool water is very dirty or contaminated, then the backwash pool could potentially reintroduce dirt instead of effectively removing it. You must require additional filtration or chemical treatment to clear the water. It’s important to balance the need for filtration with the proper maintenance of the filter system. It ensures optimal water quality and performance.

Final Words

Now, your confusion about how to backwash my pool filter has been resolved through this guide. We have discussed and elaborated you the right way of the procedure. It is necessary to imply it but in an accurate manner. That is how you can preserve the durability and integrity of your pool. So next time, when you plan to backwash the filter, keep these methods and elaboration in mind.


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