Introducing Basics Of A Sand Filter

Every swimming pool needs attention to maintain crystal-clear, hygienic water. This intended outcome is achieved through the right use of the sand filter in conjunction with water treatment using water treatment solutions.

Basic Operations in a Sand Filter:

As shown in figure 1, these are the basic Valve positions and their operations.

1. Filter mode is the primary Operation where water comes from the pump through the dial valve to the sand filter and returns to the pool.

2. Backwash is used to clean the filter as the water travels from the pump to the dial valve and then through the sand in the opposite direction to outside 

Carrying all the filtered materials which block the normal passageway of water.

3. Rinse to clean the dial valve and it should be done after the backwash in order to remove eventual impurities inside the valve. 

4. Waste / Drain water without filtering and emptying the pool.

5. Whirlpool / Recirculate is used to recirculate water without filtering it. Used only in certain conditions where the water need not be filtered or 

when specific water treatment allows you to check if the breakage of certain dial valve parts is causing sand to accumulate at the bottom of the pool. 

Also used when certain chemicals are added in the circulating line.

6. Winter mode is used while wintering which prevents eventual breakings caused by freezing.

7. Lock / Close used to clean the strainer basket which blocks all the passages of the valve.

                                                        Figure 1

Things to look out for:

Always remember to switch off the pump before changing the functionality of the sand filter.

Sand has a life span of 3 years.

Dial valve seal life span increases protection during winter.

If the pressure is still high after the proper procedures, repeat the procedures again till it is completely clean.

If the pressure gauge is broken, we can check the return of water in the pool from filtering and if it is visually weaker than before, it means you are required to clean the filter.

The grain size of the filter media used must always be larger than 0.4 mm.

Filter Media:

Sand filter media is a type of water filter that uses quartz silica sand, not just any regular type of sand as it is a great filtration element in the process that filter up particles down to 20 microns.

Quartz sand, silica sand, anthracite coal, garnet, magnetite, and other materials may be used as filtration media. Silica sand and anthracite are the most commonly used types. 

How to Change Pool Filter Sand?

1. Turn off the pump, drain water from the filter, and remove the lid or top mount valve.
2. Take out all the old filter sand, then thoroughly clean and inspect filter components.
3. Replace filter media with sand or a suitable alternative.
4. Turn on the pump and run a backwash cycle on the filter.

What can I use in my sand filter instead of sand?

Zeo Sand and Filter Glass are two alternatives to standard silica sand, and each of them can generally increase the filtration capacity of your sand filter to less than 5 microns.

How do I choose filter media?

Filter media are generally sized by porosity or particle retention. In determining the best size filter media for your process, it is important to know the particle size distribution of your product. This provides a starting point for media evaluation.

Sand filters for you;

You can buy a wide variety of sand filters from our collection of a selection of highly efficient sand filters. You can find filters that are manufactured by brands which are well-known for their high-quality products such as Hayward, Norsup, Pentair, Flotide and Waterco. You can order models made out of HDPE, PE/fibreglass-reinforced polyester, PP, and gel-coated polyester. Products suitable for various working conditions such as maximum operating temperature ranges and pressure ranges can be found here. Maximum operating temperature ranges from 35 °C to 50 °C and pressure range starting from 1.8 bar to 3.75 bar can be bought from our inventory.

Over-wintering of the filter system.

Empty the filter, pump and piping completely and protect them from frost. Please observe the following instructions:

1. Backwash the filter thoroughly.

2. Empty the pipe system. Drain the water in the pool below the inlet nozzles. (Loosen the hose connections).

3. Empty the filter system with the lower drain plug and leave it open.

4. Remove both the drain screws of the pump and the coarse filter cover.

5. Set the 6-way valve to the Filter position.

6. Put all electrical connections out of operation. If possible, switch off the fuses.

7. Pour sand out of the tank, clean and allow to dry.

 

Restart the system in the opposite order in the spring. Your swimming pool filter system will have a long service life if you pay attention to all of these things.