The process of backwashing dislodges trapped debris and contaminants, flushing them out through your value's waste line or a hose that is connected to the pool pump. When the filter media is clean, the pressure gauge is lower and water can easily flow in and out of the system.
As a general rule, you should be backwashing your pool about once a week or in conjugation with your scheduled maintenance. Another industry standard is to backwash when your filter's pressure gauge reads 8-10 PSI (pounds per square inch) over the starting level or “clean” pressure.
The backwashing process reverses the flow of water to flush out contaminants from a swimming pool filter. It should be carried out until water runs clear through the waste line.
Can You Backwash Too Much? If you backwash your pool too much i.e. time duration and/or close frequency then yes you can cause a lot of problems. Some problems that can arise from backwashing your sand pool filter too much are: Loss of water – 500+ litres of water can be lost in each backwashing cycle.
Essential Backwashing Tips
Stop it immediately after it clears. -Top up the sand in your filter after a backwash since the process will wash out a lot of it. Run the rinse setting while you top up the sand to ensure it doesn't go back to the pool.
Turn the lever to RINSE, start the pump and rinse for about 15-30 seconds. Stop the pump and turn the lever to FILTER. This is the normal operating position. Close the drain outlet valve and start the pump.
Any backwash water is to bypass the septic tank and be discharged to the drain between the septic tank and the common effluent drain. Under no circumstances should backwash water be discharged into the septic tank.
Often, excess sand gets into the wrong places when refilling and will sand to come out into the pool or out of the backwash hose. But it should go away after a few runs. In general, you shouldn't be losing sand from your sand filter. Nor should any sand be coming out during backwashing, rinsing or filtering.
Whenever the filter fills up with the dirt/debris it reduces the flow of water to your pool. Low flow = poor circulation which will lead to algae in the pool. Bottom line, the filter must be backwashed on a regular basis to ensure that your pool water is clear.
For inground pools with a sand or DE filter, the easiest way to quickly lower the water level is to place the multiport valve into the waste position and roll out the backwash hose. If instead, you have a slide (push-valve), backwash the filter to lower the water level.
Backwashing can take only a few minutes to complete, but for a typical pool, it consumes approximately 200 to 300 gallons of pool water! So, while your filter is losing unwanted dirt and debris—your pool is losing a ton of water.
Rinse runs water in the same direction that normal filtering does. Backwash runs it through the sand in the opposite direction. Rinse is to clear any dirt out of the clean side of the sand before you start sending it back to the pool.
Backwashing a sand or DE filter is a simple task. Shut off the pump, set the multiport valve or slide valve handle to the backwash position, roll out the backwash hose and turn the pump on again. Backwash for 3-4 minutes or until the water runs clear, then shut the pump off and return the valve to the filter position.
After backwashing, new DE must be added to the filter. Add the entire amount of DE the filter recommends. If you see DE returning to the pool, vacuum it to waste, after it settles. The next time you backwash and recoat, decrease the amount by 1 pound.
Overall, the lessons learned today is you should run your pool pump an average 8 hours a day to properly circulate and clean your water. The pump should push your entire pool in gallons in this 8 hour period of time. Residential pool water only needs to be turned over once daily to have proper filtration.
You should backwash your DE pool filter about once a month during pool season. In addition to the regular schedule, you'll want to perform additional backwashing if: You've been running your pool filter for 48 hours straight. This can cause a pressure build-up, even if the filter grids look clean.
In most cases, the cleaning time is set in the early morning when everyone is asleep. Every 4 to 7 days, the backwashing system gets activated and completes the cleaning process by itself. You do not need to manage the backwashing system personally.
After a backwash, to get the amount of DE powder, simply take the recommended amount of DE powder for a new filter and multiply it by 0.8, or 80%.
Backwashing a filter too frequently will keep the sand so free of dirt buildup that it will not have the ability to remove the smaller particles of dirt and they will simply pass through sometimes causing cloudiness in water.
Replacing a sand filter in your pool has a similar cost of installing a new one. You will pay for the unit itself, with sand models ranging from $300 to $1,200 and the professional installation. In some cases, you may be able to replace just the sand, which only costs about $25 to $35 for a 50 lb. bag.
If you see it blowing out into the pool, something is broken. The most common problem is a cracked lateral, which is one of the perforated pipes at the bottom of the filter that catches water that has circulated through the sand.
Backwash water must be collected, contained and discharged to the sanitary sewer, if available, or to a vegetated area contained within your property. Cartridge filters should be rinsed in a sink, bathtub, or over a lawn or other vegetated area.
In order to prevent residual blow back into the pool, once you've finished backwashing it's highly advisable to rinse the filter. Just as the backwash lifts and flushes the sand, the rinse resets the sand to its original position for optimum filtration.
If you do have this option, it is highly recommended that whenever you have algae, you will need to vacuum to waste. This option allows you to vacuum the algae up and send it out through the backwash line, avoiding getting algae into your filter sand.