Deep clean gone wrong

[mikeqf]

In another thread I recently resolved a bad flow switch problem with our SWG, and while doing research I read a lot about deep cleaning the sand filter. It has not been done in our years of ownership and all the things I read suggested doing it once a year.

I disconnected the sand filter - a Pentair Sand Dollar SD80 - from everything and proceeded with disassembly. Got the clamps off just fine, and with some slight turning and pulling the valve assembly started to come up. Here is where I think things didn't happen as they were supposed to, as the valve assembly did not come off of the stand pipe. as I pulled up, the laterals came up out of the sand. (see picture) The videos I watched showed valve coming out without the standpipe, but for the life of me I can't get the pipe to budge out of the valve.



From more reading it seems I'm going to have to remove the sand to put the laterals back where they belong, but the only way I'll be able to get the sand back in is with the valve off the pipe. Am I missing something really easy? I'm hesitant to pull too hard and cause damage to the laterals.

 

[mikeqf]

Update - some gentle tapping with a rubber mallet loosened it up. The question still is - should it have lifted right off?

 

[mknauss]

Update - some gentle tapping with a rubber mallet loosened it up. The question still is - should it have lifted right off?

Good you got it off.
From the youtube's I have looked at, you twist it and it comes right off. I would sand down the standpipe so it slips on/off easier for the future.

 

[zea3]

There should be an o-ring at the top of the standpipe. Put some silicone pool lube on it too.

 

[CrystalRiver]

I've changed out the sand on a filter. That's basically what you will be doing, whether you reuse your current sand or get new.

There should be a drain plug at the bottom of the filter. Open that and let it drain. The longer it drains the better. Any water that doesn't drain out, you have to lift out. Figure out where you are going to put the sand - buckets, a wheelbarrow, a tarp on the lawn, it's up to you. Then get yourself something to scoop with. I used an old plastic kids' cup. Scoop and dump, scoop and dump, all the way to the bottom of the barrel. Once it's almost empty, you can hose down the inside of the tank if you want to gather the remaining sand together.

Refilling: get all the sand out from where the lateral assembly sits. Put the cap back on the tank drain, and fill it about half way with water. Get the lateral assembly in there, centered. Put something over the center pipe so no sand goes down it - I used a PVC cap the next size up. My filter originally came with a little cardboard hat for it. Then it's more scooping and dumping, scooping and dumping, into the tank this time. Don't dump too much too fast, lest the weight break laterals. If you're using a cup and have the tank half full of water, no worries. If you're dumping a bag of new sand, go slowly, and wear a mask for the dust (carcinogenic).

 

[mikeqf]

Thanks everyone for your help. That was not a fun job. Took me a while to realize I could unscrew the laterals and get the standpipe out, then scooping the sand just took a long time. I finally got it back together and we're working again.