D.E. Filter Failure

[Stephan]

Hello everyone!
This is my first post to this forum, although I have been reading y'all for a while now and have read more than once all the good tips from the Pool School section.
I have a 28,000 gallons (approx.) quartzite pool in Fayetteville Georgia (Atlanta suburb) with a 60 sf D.E filter.
Early this morning whilst my pump was running, I heard a very loud whistling noise coming from the pump: the filter tank pressure valve broke and water was "geizering" a good 15 feet through it. Upon further examination (at sun rise), the whole pressure valve blew up (including gauge), but more important, the fiber glass upper tank is cracked.
The pool was built about 5 years ago (previous owner had it done) and this is my 3rd season as an owner. I am actually a little bit surprised that I have already had to replace a pump motor (Paintair) and the D.E. grids. Now the tank fails! (I wounder if used equipement was used.) It is a Purex Nautilus NFS 60, and unfortunately it doesn't seem to be manufactured anymore. A quick internet search for parts returned around $80 for a complete pressure valve assembly and close to a $1000 for the upper tank!
So here are my questions to you:
1. How come the pressure built up so high that it cracked the tank? I backwashed the filter no later than this weekend and the whole filter was cleaned in May. To be honest, I noticed a little leak at the base of the pressure valve assembly that I was going to address at the end of the season.
2. Are the prices I found in the ball park or is there another way to fix this mess for cheaper?
3. Since my filter does not seem to be manufactured anymore, should I take this "opportunity" to replace the whole filter by something newer instead of just replacing parts? If yes, what system do you recommend? Is D.E. worth the aggravation to have to deal with the frequent maintenance or a sand filter, although not as efficient, a better compromise?
4. Since I am not going to have any filtration for a few days (at best) and it is still pretty warm here in the South (pool temp was at 84F this weekend), what can I do to make sure my pool does not turn into a swamp? (I use chlorine.)
Thank you all in advance!

-Stephan.

 

[JohnT]

Welcome to TFP.

Hard to guess what might have caused it. What model pump do you have? What kind of pressure did you normally run at? Any kind of restriction from the pool returns back to the inside of the filter could have led to pressure buildup, and it's possible that your leak was a crack that failed suddenly.

You can replace the whole filter for less than you are talking for the parts.

You could probably plumb a bypass around the filter and just circulate the water. It won't remove debris, but it will circulate the chemicals. You might consider a T for a pressure gauge so you know what's going on.

 

[duraleigh]

Welcome to the forum :lol:

I have no idea how the tank failed. A pool pump can only produce about 35-40 psi and filters are generally tested to 50+ so something must've "worn out" in the filter.

Replace the entire filter. Trying to patch a cracked vessel is simply not worth the hassle. You can get a brand new filter and multi-port valve for far less than replacing that cracked vessel.

If you get 100 recommendations for the type of filter, you will get 100 different opinions. Almost everyone likes the type they currently own so you will have to make your own choice. Each has some advantages and disadvantages but they all work.

 

[Stephan]

Thanks all for your prompt answers.
I do have a multi-port valve so I'll set it on Recycle for now.
The PacFab/Purex/Pentair Nautilus FNS60 (tan) filter I have is discontinued and buying a replacement top tank with air relief assembly runs just under $800. But a current modele Pentaire FNS60 top tank with air relief assembly is about $300 (go figure.) I can't say if the new top is compatible with my old bottom. If I could find an old top for the price of a new one, I'd be a happy camper. Maybe a professional here can help me?
Thanks!

 

[waste]

Welcome to TFP!!


I've got to wonder if you somehow had the return valve(s) closed ?

Other than that, I find it hard to believe you built up soo much pressure.

If replacement costs come close to a the cost of a new filter, I'd go with a new filter - if the top went, who knows how much longer the bottom will last.

Whichever way you handle this, we need to be sure that it doesn't happen again! As such, any additional info you can give us will be invaluable

Thanks for coming here, we'll help get you all straightened out

 

[zea3]

If you get a lot of dust and dirt in the pool or have overhanging trees then I would stick with a DE filter. If your pool stays relatively clean and had taken a long time to build up pressure in the past, then I would go with a 300lb sand filter. If water conservation is an issue then you may prefer a cartridge filter.

 

[Stephan]

Thank you all for your inputs. I am going to have a professional look at it, and will report here the outcome.

 

[Guest]

Good luck!

When I bought my house, some parts of my DE filter were missing. I replaced them as I could do it immediately, but today I know that by shopping around I could've done much better buying a whole filter. There are some on ebay, but also on craigslist, amazon, and I even saw my filter at a flea market!

You can add bleach and stir it up temporarily with a brush or other implement on a long pole, or stir it up with a submersible pump. Good luck!

Sue

 

[Stephan]

I just talked to my pool guy and he recommends changing the whole filter as expected. Considering my configuration (no leaves or dust), he recommends switching to a sand filter (500lbs). It seems to be much easier than a DE to maintain and clean and since my pool remains pretty clean, I don't really need the extra filtration the DE brings. All that comes to a cost of $1500 including filter, sand, piping, new multi-port valve and labor. I was not expecting this type of expense but the pool needs to be fixed anyway and I have already worked with this guy and he seems very fair price wise and knowledgeable. Work will start on Friday, unless you guys tell me that the solution or its price is totally crazy

 

[CUTiger78]

I just talked to my pool guy and he recommends changing ... to a sand filter (500lbs). All that comes to a cost of $1500.... Work will start on Friday, unless you guys tell me that the solution or its price is totally crazy

I think the price is totally crazy!

I replaced the sand filter for my 36,000 gallon, inground, gunite pool in August '09 with a 300 lb sand filter, a Hayward S244T. The filter cost about $300 delivered. I used 150 lbs of Zeosand at a cost of around $100 (sand probably would have cost $50). Plumbed it in myself with PVC and some flex pipe, maybe $20 worth of pipe. I'm not much of a DIY'er, but even I can work with PVC.

So, IMHO, 500 lbs is too big & $1500 is too much.

Good luck!

 

[guamguy]

I wouldn't say 500 lbs is too big, but $1500 is too much. With filters, bigger is better, more efficient, less backwashing. My pool is just under 13K gallons with a 325 lbs sand filter. I wish I had a bigger filter

 

[Noggin]

I'm going to go with these other guys and say do it yourself, unless you're heck bent on supporting someone else instead of yourself. Jump in feet first and just do it, that's how you'll learn... and save about $1000. It'll probably take you somewhere between 4 and 8 hours if you go slow and carefully. Would you do manual labor for $125 an hour for 8 hours? How $250 an hour for 4 hours? If you still insist on hiring a pool guy to do the work, give me a call. I'll do the labor for a bargain price of $100 an hour.

 

[Stephan]

OK, thanks for the input. I'll see with my guy if he can come down a little.

 

[bk406]

I'll chime in and agree with the others. $1500 is way over priced. Depending on the size of filter, you can DYI pretty easy for around $600, maybe less.

 

[Stephan]

I think $500 to $600 for a DIY job is quite optimistic. A Pentair or Hayward 500lbs sand filter runs between $600 to over $1000 depending on modele (from what I can see on the net.) Sure I see some $250 filters, but not in my size. Add to that $100 for the multi port valve, $100 for sand, $50 for miscellaneous things, shipping and taxes, and you are at a minimum at $1K. But I'll get him to come down a little.
Thanks!