Sand Filter systems are a popular type of swimming pool filter among pool owners, especially for those who have larger swimming pools. As the name indicates, this type of filter cleans your pool’s water with sand. The sand sits in the filter tank and cleans your swimming pool as the water flows through it, then the clean water is returned to the pool. Sand Filters have the largest micron rating, but over time Sand Filters collect more debris and dirt as it cleans which causes the filter to become more efficient.

This type of filter is fairly low maintenance, however backwashing is required in order for the system to function properly. There are two different valves that can backwash Sand Filters, so follow the steps below depending on what type of valve you’re using. No matter which type of valve is used to backwash, the first thing you need to do is turn your swimming pool pump off and pull out the hose if you will be using it.

Backwashing With a Side Valve
To begin backwashing with a side valve, unlock the T handle and open the air bleeder on the filter. Turn the pump on, let the hose fill up with water and backwash the Sand Filter for about three minutes, or until the water is clear. When the water is clean turn the T handle back, turn the pump on and be sure the pressure has returned to a low setting. If the pressure is low, you are finished backwashing, but if it’s high then backwash your Sand Filter again.

Backwashing Using a Multiport Valve
Again, be sure to turn the pump off and remove the hose if you are going to use it to backwash. Next, turn your valve handle so it is in the backwash position, open the air bleeder and turn your pump on. Let your Sand Filter system backwash for about three minutes or until the water is clear, then shut off the filter and move the handle back to the rinse position to let your system rinse for 20-30 seconds. Turn your pump off and position the handle back to filter, turn your Sand Filter back on and take a look at the pressure. A lower pressure means your filter is clean, but if the pressure is still high you need to repeat the backwashing process.

After a second round of backwashing with a side valve or multiport valve, it is not uncommon to find that the pressure is still high. If you have noticed this, be sure to check for any kinks or clogs that may have happened during backwashing. Simply clear out your hose and check to see if the pressure has returned to a lower level.

Sand Filters are low maintenance because the sand in the filter tank only needs to be replaced every three to five years. A sign that your sand needs to be changed is when you have to backwash your filter more often than normal. When you’re replacing the sand, be careful to not crack any parts inside the tank, as this can lead to expensive repairs. Changing the sand is a fairly simple process, but taking the time to do so correctly can save frustration later. For more information about Sand Filters, backwashing or other pool maintenance questions, don’t hesitate to contact the professionals at LinerWorld!