How to Backwash a DE Filter

de-filter arizona pool careIn this guide, you will learn the the steps to successfully backwashing a DE filter, and how often you should be doing this. First, let’s start with how to backwash a DE filter:

How to Backwash a DE Filter in 5 Steps

1. Turn off your filter system and turn your multiport valve to the backwash position or open your backwash gate if you have a push / pull valve.

2. Turn your system back on and run it for about two minutes letting the water flow out of the backwash valve or port. It would be a good idea to use a backwash here.

3. After two minutes shut your system off and if you have a multiport valve, turn it to the rinse position and turn your system back on and run it for about a minute. If you have a push / pull valve just run in for about another minute.

4. Now turn your filter system off and turn your multiport back to filter or shut your push / pull valve.

5. Turn your system back on and add fresh DE Powder to your skimmer depending on your filter’s instructions.

How to Backwash or Bump a Hayward DE Filter

Turn your filter system off and open the backwash valve. Using the bump handle, bump the filter slowly 15 times. With the backwash valve still open turn your filter system back on and let it run for about two minutes. This will rinse out all of the DE that you shook off the fingers in your DE Filter.

Turn the filter system off and repeat this again to ensure all of the DE has been rinsed out. Bump it slowly 15 times and turn your system back on for about a minute or so.

Shut your filter system off now and replace the cap or close off your backwash valve and now start your filter system back up. Add more fresh DE to your skimmer, add it slowly to avoid a clog!

How Much DE to Add After Backwashing

The first thing you need to determine is the square footage of your DE filter. If it’s not listed on the side of the tank, you can easily do a Google search to find out or contact the dealer you bought the filter from.

DE is measured in pounds, it is recommended to use a 1 lb DE scoop, however, if you’re in a pinch, you can also use a one-pound empty coffee can. Here is a chart that lists both:

Standard DE Powder Dosage Chart

Standard DE Dosage Chart

How Often Should You Backwash a DE Filter?

To determine when it’s time to backwash, you should look at your pressure gauge. The pressure gauge is there to tell you when the pressure inside the tank increases. The more dirt and debris your filter has collected, the more your pressure will go up.

After a fresh backwash, or at the beginning of the season, make a note of what your pressure gauge reads — this will be your normal filter pressure.

If and when your pressure gauges reads 8-10 pounds over the normal running pressure, it means it’s time to backwash. For instance, if your filter is running at 15 PSI normally, and it climbs up to 25 PSI, you should backwash it.

(source: swimuniversity)

Here’s a great video on how to backwash a DE filter: