Replacing Sand

[pinguy]

I'm working with a commercial pool that is in rough shape. We have 3 large Pentair Triton II sand filters that I'm thinking are about 25yrs old. I don't think they've ever been cleaned or had a sand swap.

Doing some research on here, most people seem to be of the opinion that sand never seeds swapped - just cleaned. I think it this situation it makes more sense to swap the sand, as labor is the biggest expense.

So my question, what all is involved in replacing sand? Is there anything else I should be doing with these filters, like a deep clean of sorts?

I had a commercial pool contractor come out and give us a quote .... $5300 for new sand and 3 new multiport valves (ours are in bad shape). I think this is really high, especially when we have a crew of mechanically/plumbing inclined guys who can always use a winter project. If it is an easy process, we could save a good bit of money doing it in house...but I also want it done correctly.

 

[Texas Splash]

In the majority of cases we recommend a deep clean as seen on the TFP Deep Cleaning a Sand Filter page because sand doesn't just go bad unless previous owners introduced some chemicals that may have compromised it's ability to filter. But if you do decide to replace the sand, it should simply be a matter of getting the old stuff out, inspecting/cleaning the interior, laterals, and stand-pipes, then carefully refilling with the new sand as required. If the entire multiport valve(s) must be changed, it certainly can be a DIY project. $5,300 seems like a lot of $$$ to me. Even if we use a relatively high estimate of $200 per valve $600 total) plus the silica pool sand required, I can't imagine getting half that high as the contractor quoted. I'd let your crew do the work and use some of the saved money for pizza and liquid refreshments.

 

[pinguy]

In the majority of cases we recommend a deep clean as seen on the TFP Deep Cleaning a Sand Filter page because sand doesn't just go bad unless previous owners introduced some chemicals that may have compromised it's ability to filter. But if you do decide to replace the sand, it should simply be a matter of getting the old stuff out, inspecting/cleaning the interior, laterals, and stand-pipes, then carefully refilling with the new sand as required. If the entire multiport valve(s) must be changed, it certainly can be a DIY project. $5,300 seems like a lot of $$$ to me. Even if we use a relatively high estimate of $200 per valve $600 total) plus the silica pool sand required, I can't imagine getting half that high as the contractor quoted. I'd let your crew do the work and use some of the saved money for pizza and liquid refreshments.

They quoted a fair price on all the materials (will probably still get the materials from them), but the labor was crazy high....like $3200. That would be like paying a crew of 3 $130/hr for a day of work.

They had gravel on the list of materials ... anyone have an idea of where that comes into play?

 

[pooldv]

It is less work to deep clean the filter than it is to replace the sand. Unless the sand is glued together by pool store chems.

Deep Cleaning a Sand Filter

 

[YippeeSkippy]

The gravel is something I'd never heard of before reading it here on TFP. You can add it to the bottom of the sand filter and put the sand on top of it. I'm unsure if it is just to some particular filters or if universally possible....but will research this and get back to ya.

 

[Texas Splash]

They had gravel on the list of materials ... anyone have an idea of where that comes into play?

Some people will put a layer of pea gravel at the bottom of the filter to support/protect the laterals. They also find it helpful at times preventing sand from easily blowing-back through the lateral openings.

Also see THIS POST.

 

[YippeeSkippy]

The gravel is something I'd never heard of before reading it here on TFP. You can add it to the bottom of the sand filter and put the sand on top of it. I'm unsure if it is just to some particular filters or if universally possible...

Yup- read this --> Gravel in Bottom of Filter

 

[pinguy]

Apparently they make instruction manuals for these things

 

[Texas Splash]

 

[pooldv]

What? Now you're breaking all the rules!

 

[JoyfulNoise]

Keep in mind this is a public/commercial pool. So while we might not recommend that residential pool owners change sand, this may be a decision that is not within the OPs control.

Pinguy - it's a big Olympic style pool, right? What's the total volume? Post some pics so everyone can get a feeling for the scale of the job.

Adding gravel is probably the right way to go because you'll have a high bather load in this pool and you'll want as much throughput in these filters as possible.

 

[pinguy]

Yes, the pool is 1/2 olympic size and around 120,000 gallons.

Since the pool is semi-public, I don't want to post an identifiable pic (I'm just paranoid) ... but the public doesn't see the equipment pad, so I'll post a pic of that:

That old pump runs 24/7. The pool is chlorinated with a stenner pump hooked up to a 120gal holding tank. I'm told it was built in the early 50's, but it could easily be older than that. Yes the pump basket is being supported by a rock

 

[kadavis]

Changing sand in these filters isn't hard just tedious and dirty. What size do you have the 100 or the 140? For 5,300 you could buy three new Tr-100 w/sand and valves. Invest in a large capacity vacuum and it would go faster

- - - Updated - - -

THS Series Horizontal Sand Filter. or you can get one of these badboys

 

[pinguy]

Changing sand in these filters isn't hard just tedious and dirty. What size do you have the 100 or the 140? For 5,300 you could buy three new Tr-100 w/sand and valves. Invest in a large capacity vacuum and it would go faster

- - - Updated - - -

THS Series Horizontal Sand Filter. or you can get one of these badboys

We have 3 TR140's --- definitely going to do this in house ... and maybe consider a career change to the commercial sand replacement industry :-?