How To Backwash a Sand Pool Filter

Sand swimming pool filters should be backwashed and cleaned on a routine basis. But cleaning a sand pool filter too frequently can lead to poor water filtration and undesirable water clarity. The most common indicator of when a sand filter needs to be cleaned is when the filter gauge reading increases by 10 psi. Simply monitoring the pool filter gauge will let you know when it is time to backwash your sand filter. When that time comes, it is a very simple process and should only take 10 - 15 minutes to complete.

Turn the Pool Pump Off - ALWAYS turn all the pool equipment off and make sure it will not automatically turn on during the filter backwash process.

Prepare the Pool - prepare the swimming pool by verifying the water level in the pool is sufficient and all skimmer and pump baskets are free of debris.

Backwash - ensure that the suction and backwash lines are open so water can freely flow in from the pool and out of the backwash line. Again, before moving the control valve on the sand filter to the backwash position, make sure the pool pump is off and will not turn on automatically during the process. Move the control valve to the 'Backwash' position. Stand clear of the filter and start the pump. Let it run for 3 to 5 minutes or until the backwash water is running clear. When the backwash water runs clear, turn the pump off.

Rinse - With the pump off, move the control valve position to 'Rinse'. Turn on the pump and run the rinse cycle for 30 seconds to 1 minute. When the rinse cycle is complete, turn the pump off.

Restart the Pool Pump - with the pump off, move the control valve back to the 'Filter' position. Open the manual air bleed valve on the top of the filter. Turn the pump back on and monitor the manual air bleed valve until a steady stream of water emerges. When this happens, close the manual air bleed valve.

Record the Filter Gauge Pressure - The filter has now been cleaned and is back on its normal filter cycle. Record the filter gauge pressure for future use. When the filter pressure increases by 10 psi, it will be time to backwash the sand filter again.

Remember it is not good for the sand filter or the pool water to backwash the filter too often. But neglecting to backwash a sand filter when needed will not only lead to a dirty pool, but can also damage to the filter. The best way to know when the filter needs to be cleaned is to make sure the filter gauge is in good working order and to monitor it at least once a week for increases in filter pressure.

These instructions will apply to most modern sand pool filters. Older sand filters may not be compatible. Always consult the owners manual for cleaning instructions for specific sand filter models.