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I have a Purex Triton Nautilus FNS DE filter. I need to get the grids out to find a leak. I removed the two long bolts - what else need to be detached/unscrewed to get the grid cap off?

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SOURCE: How do I backwash my Pentair Vertical Grid DE filter?

For instructions on backwashing and other trouble shooting, you need an Owner's Manual. You can find one online at the following link:

The way you backwash this filter is easy once you get the hang of it!

The first thing you will do is turn off the system, change the valve position to the Backwash position. If you have a Multiport Valve, you will press down on the handle and spin it so that the knotch is pointed to BACKWASH. If you have a Slide Valve, only has two positions, up and down, you turn the handle so that the metal pin is out of the holder and move the handle in the opposite direction. You will need to turn the handle to lock the pin into position.

Once this is done, you will turn on your pump. Pentair recommends that you backwash for 1 minute, then turn off the pump.

If you have the Slide Valve, you will put it back into the FILTER position and then turn the pump back on for 1 minute. If you have the Multiport Valve, you will put it in the RINSE position and then turn the pump back on for 1 minute.

Pentair recommends that you do this cycle a total of three times, backwash/rinse, backwash/rinse, backwash/rinse. AFTER the third time, you will need to open the Air Release Valve at the top of the filter while the pump is OFF and the valve position in back on FILTER. Once this is done, turn on the pump. When you have a steady stream of water coming out of the Air Release Valve, close that up. This way you have no air in the system.

Now, you will mix your DE "Slurry" in a bucket. Depending on your model of filter, you will measure out your DE and mix with water to the consistancy of milk. **IF it is just a backwash, you will only add 80% of the original amount of DE. You only add the total 100% of DE when you completely take the filter apart and clean it out.**

You will slowly pour the slurry into the skimmer that is closest to the pump. This will allow the DE to evenly coat the grids in the filter. Wait about 5 minutes and then check the pressure gauge on the filter. Once the PSI reaches 8 to 10 PSI above this number, it is time to backwash.

Posted on Jul 09, 2009

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