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why does my pool filter spit out sand


Why Does My Pool Filter Spit Out Sand?

Pool filters are essential in maintaining a clean and sparkling pool. They help keep the water free of dirt, debris, and other contaminants that can make swimming unpleasant. However, sometimes pool filters may begin to malfunction, and sand ends up getting discharged into the pool. This can be frustrating and worrying, especially if you have no idea why it's happening. In this article, we'll explore the reasons why your pool filter may spit out sand and what you can do to solve the problem.

Understanding Your Pool Filter

Before diving into the possible reasons why your pool filter is spitting out sand, let's take a moment to understand how pool filters work. In-ground swimming pools typically use one of three types of filters: sand filters, cartridge filters, or diatomaceous earth (DE) filters.

Sand filters are the most common type and are often installed when the pool is built. They work by using a special type of sand called silica sand, which serves as the filter media. The sand traps dirt and other contaminants as the water flows through it, and the clean water is then returned to the pool. Over time, the sand can become clogged with debris, which can reduce its effectiveness and cause the filter to malfunction.

Possible Causes of Sand Spitting

1. Broken Laterals

Sand filters contain a series of tubes called laterals that help distribute the water evenly across the sand. If one or more of these laterals break, sand can escape through the openings and into the pool. You may notice sand in the pool or a decrease in the water pressure.

Solution: Replace broken laterals.

2. Cracked Filter Tank

Typically made of fiberglass or plastic, the filter tank can become cracked due to temperature changes or other environmental factors. When this happens, sand can leak out through the cracks, resulting in sand in the pool.

Solution: Replace the cracked filter tank.

3. Wrong Sand Type

Using the wrong type of sand can cause your filter to malfunction. The sand used in a pool filter should be specifically designed for pool use and be high quality. If you fill your pool filter with regular sand, the sand particles can be too fine or too coarse, which can result in sand making its way into the pool.

Solution: Replace the wrong sand type with pool filter sand.

4. Improper Backwashing

Backwashing is the process of removing the dirt and debris that has accumulated in the filter media. Not backwashing enough, or improper backwashing, can cause sand to be discharged into the pool instead of being removed.

Solution: Follow the manufacturer's guidelines for proper backwashing.

5. Broken Multiport Valve

The multiport valve is responsible for controlling the water flow in and out of the filter. A broken valve can result in sand being discharged into the pool.

Solution: Replace the broken multiport valve.

Preventing Sand Spitting

To prevent sand from being spit out of the pool filter, you should follow these tips:

- Regularly check and clean the pool filter.

- Backwash the filter according to the manufacturer's guidelines.

- Use the correct type of sand for your filter.

- Keep an eye out for any cracks or broken parts in your filter.

- Replace any broken or malfunctioning parts immediately.

In conclusion, if your pool filter is spitting out sand, there are several possible causes. By understanding how your pool filter works and following the above tips, you can prevent sand from being discharged into your pool and maintain a clean and sparkling swimming pool all year round.


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