Changing Filter Sand

[RRD]

Last summer I had to replace the pressure gauge/release valve on a Pentair 100c filter. When we opened up the cap (which was a 6 hour awful task) the inside of the filter smelled horrible, and I could see the inside of the filter was a pretty big mess. This is a free community children's pool that gets some heavy usage, so I am assuming that I need to change the sand. It has not been changed in at least 10 years. Possibly in more than 15 years. Could be as long as 30 for all I know. Also, the laterals may need replacing as the filter does have sand shooting issues, and has for a while. My first question is, am I correct in assuming that the Sand needs to be replaced?

Today, I went to take the caps off the filters so I could dig out the sand, (there are two children's pools), but I couldn't. Both pools, the cap is stuck on there. I tried using a hammer and a wood block with the filter wrench with no luck. Last year it took three of us to get it open and I have somebody coming to help me tomorrow, so hopefully, I can get it off. My second question does anybody have any ideas or advice for getting the caps off?

Finally, the 100c is a big filter, and that seems to be a pretty small hole in the top. Anybody have any experience with this model? I'm not totally sure I'll be able to dig the sand out, or reach in and take out the laterals to examine them.

Also, additional information, one of the filters has had it's cap replaced with a different model cap, and no, I do not know why somebody would do that.

 

[tim5055]

All I can say is sand doesn't wear out. Search on deep cleaning the sand.

Now, cracked/broken laterals do need to be repaired which will involve removing sand.

 

[JasonLion]

A good way to deal with the small opening is to use a shop vac to remove the sand. Assuming you do need to remove it, which isn't at all clear.

 

[RRD]

How can I tell if I need to remove it? Low flow rate? Is there any way to tell by looking at the sand if it needs to be changed?

And Tim, Deep Cleaning involves opening up the cap and sticking a hose in the filter and overflowing it, yes? I'm asking because this filter is inside. It's not un-doable, I just wonder if it would be easier to replace the sand than empty out the building, deep clean the filter, and then clean out the building from the stuff that was inside the filter.

 

[JasonLion]

If the sand forms clumps that can't be very easily broken up by hand it should be replaced. If it is just full of crud, it should be cleaned.

I suppose there are situations where replacing the sand might be easier, but removing replacing the sand is real work and cleaning is fairly easy. Most indoor filters are in an area where spilling water on the floor is not an issue at all, it just goes down the drain. If that is not true where you are, the balance might come out differently.

 

[RRD]

Got it. I'll take a look once I finally get those awful caps off tomorrow. Is there any way to make sure it will be easier to remove them next time? When I opened the one up last year I made sure to use plenty of lube, and it is definitely on correctly, but it's still jammed real tight.

And there's no drains. It's just a concrete floor. I don't have to worry about getting water on the floor, I just need to empty all the stuff around the filter out of the pool house and then sweep it out or hose it out after I'm done, and put everything back in.

 

[RRD]

I tried to deep clean one of the filters today. Unfortunately I couldn't overflow the filter. The water just ran right through the multiport valve, which was on "closed," and backwards into the filter basket as well as out the waste line, and into the returns. I replaced the spider gasket a little less than a year ago, and when I opened up the multiport valve, nothing looked wrong with it. The plastic on the handle that contacts the gasket doesn't have any grooves or anything like that. Should I just lube up the spider gasket and handle?

And just to clear it up ahead of time - the filter is not on and there is no water in the pool, (Aside from the water from the multi-port leak).

 

[RRD]

Nevermind, I figured it out. I've been deep cleaning for over an hour now with 4 hoses. There's still junk coming out. This filter hasn't been cleaned for 15 years, possibly for over 50 years.

 

[JasonLion]

We have been seeing a few of those recently. They either result from not backwashing for long enough each time, or from the pump being too small to properly backwash the filter.

Once you get it properly cleaned out it should filter quite a bit more effectively than it did before.

 

[pooldv]

Here is the deep clean thread

http://www.troublefreepool.com/threads/73192-Deep-Cleaning-a-Sand-Filter