Pentair VS settings for backwashing DE filter?

[Killer95Stang]

I just backwashed my DE filter for the first time since pool construction finished last week. Holy Crud what a pain in the arse! I need to find a better way to backwash the filter, because what I did today will no work!!

So.. I thought I could handle backwashing the filter.. heck, I watched enough Youtube videos and I just finished reading the How-to article that I found on the board. So I went to my local pool supply and picked up a few supplies to get the job done.

What I have:

- Pentair VS pump
- Pentair FNS Plus 60 DE filter
- 25 bag of DE powder
- 2" x 50' roll of backwashing hose + clamp

I planned on backwashing into my 3" irrigation drainage system for the first time, because I was not sure if that much water flowing through my house drains (I have a backwash P-trap) would cause any problems. I'm sure glad I did this, because I probably would have had a foot of standing water in my house if I didn't.. lol.

So I started by cleaning all the baskets and lubing the seals before I put the pumps covers back on. I also cleaned the skimmer. I then primed the pump to make sure their was no air in the system. I then pulled up the lever on the filter and made sure the hose was connected, before unleashing the hounds! First trial. Put the automation in service mode then selected high speed for the pump and hit the button. Hose flew off at the filter and DE powdered backwash water started flowing!! Second attempt, I made sure the hose was secured and let her rip again. I had the hose extend and set to empty into the irrigation drains. That did not work... I've run plenty of water through the irrigation system, but the amount of flow from the VS pump is too much for 3" piping. I had water shooting up from two other drains.

So, here's my question. What speed on the pump is required for backwashing DE filters? The VS on high speed is a lot of water. Also, is their a setting where the VS pump doesn't try to prime the pump? Even if I selected lower speeds, the pump always starts out on high before it settles down to the lower speed. That is probably what caused me the most trouble.

In the end I got it done, but I also cleaned about 200 feet of sidewalk in the process.. I can't do that again...

Thanks...

 

[jblizzle]

LOL ... I can just picture the white water flying everywhere.

Just wait until you take the filter apart to do a thorough cleaning (should do it once a year) ... that is a fun mess as well.

I have no experience with the VS pumps, so I am not sure of what to suggest to help you out ... someone should be along shortly with some ideas.

Not sure why the 3" pipe could not handle it ... you are running it through smaller pipes for the pool, although granted at higher pressure.

 

[JasonLion]

There is no way to avoid priming, but you can control the priming speed. There is a setting on the pump that lets you adjust the priming speed. You need to turn that down to somewhere in the 2000 to 2400 RPM range. You should also use a speed in that range to backwash the filter.

 

[Killer95Stang]

Thanks for the suggestions... I'll set the priming speed and try to do it next time around 2000rpm... Now for my next trick... getting the CYA to dissolve!

 

[jblizzle]

If you squeeze the sock (or whatever) a few times every time you walk by, you will help the process speed up a bit.

 

[pwrstrk]

Do you have it in a sock in front of return or in skimmer basket? If you do give it squeeze every so often.


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[pwrstrk]

Got beat'n to it


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[Killer95Stang]

I figured out the squeezing part.. I just have to do it a little more frequently. What I did was fill two socks, then hung them with the lid of skimmer suspending them in the water.

I used these tactical socks. The packaging said they were "High Speed"... guess not..

 

[jblizzle]

Nice!!! They might dissolve faster suspended in front of a return jet in stead of the low flow through the skimmer.