Filter delivers dirty de

[FRANCIS]

Incorrect - Dirty DE enters the pool thru the return [eyeball jets] momentarily when the pump starts up after a period of downtime. When I say 'momentarily', it lasts a few seconds - enough for a big ugly plume of green to emerge. Once the DE re-coats the grid, the water runs clear. This is killing me. I can't allow the time clock to automatically start the pump. I need to do it manually so I can divert the slug of dirty water thru a drain temporarily.

[CarlD]

Unfortunately, it looks like most of our experts on plumbing and filter issues (other than sand) may have checked out for the season.

[SunnyOptimism]

I know this sounds like generalizing but something has to be cracked, loose or torn in some way. Or there's an o-ring or gasket somewhere that is not sealing.

What you're describing is a transient situation where the pressure at start up is low allowing the "thing" that is not sealing to pass DE. Then, once the system pressurized and the DE re-coats everything, the "leak" is plugged. Remember that DE is just extremely fine silicate shells of dead marine algae. The DE particles can be as small as 3 micrometers in size but are typically 10-100micrometrs. This powder is so fine that even the smallest tear, crack or unsealed surface can allow it to pass.

So, sorry for being overly broad and not very helpful, but something is not sealed right. Looking at the design of this Hayward filter, I guarantee there's a well known engineering flaw in there somewhere. I have a Pentair QuadDE filter which is just a hybrid cartridge filter that uses DE. I like the design as there are only four cartridge units that need to be properly seated and sealed making it a low complexity design. Also, there's no mechanical bumping, just backwashing.

Keep posting results and I hope someone else here with a similar DE filter can chime in to help.

[FRANCIS]

When the pump kicks on after being off for some time, the DE particles and the dirt particles that were laying at the bottom of the filter tank are now racing back up to the grid fingers - correct? But in doing so, some of the dirt passes thru the fabric before the DE does a complete re-coat. So maybe this filter has an inherent design flaw and it's been doing this blowback since day one - but i have only noticed it recently when i walked past the returns after i activated the pump?

[CarlD]

I doubt it's an inherent design flaw. More likely a defective unit or a too-big pump. It's also possible it was initially set up wrong and was damaged.
I don't know if a total tear-down and rebuild is worth it, or if you should just consider replacing it with a bigger capacity unit, and consider switching to a sand filter.

[SunnyOptimism]

When the pump kicks on after being off for some time, the DE particles and the dirt particles that were laying at the bottom of the filter tank are now racing back up to the grid fingers - correct? But in doing so, some of the dirt passes thru the fabric before the DE does a complete re-coat. So maybe this filter has an inherent design flaw and it's been doing this blowback since day one - but i have only noticed it recently when i walked past the returns after i activated the pump?

I don't think that's how my DE filter works. My Pentair has four cartridges in it that the DE sticks to and accumulates on. Perhaps some DE floats off the cartridges after pump shutdown, but I believe most of it stays on the cartridges.

If Hayward intentionally designed their filter to lose the DE costing after pump shutdown, then I'd say that's a pretty poor design. However, since it is a bump-style DE filter, that just might be the case.

With all that said, the fingers should not let DE pass through them. If that is truly what's going on here, then I'd say you need to replace the grid assembly. Is that a replaceable part? Any idea how much that costs? As annoying as it is, I think this warrants a call to Hayward to see what they recommend.

[FRANCIS]

it's cheaper to buy a new filter than replace the 120 flex tubes @ 6 dollars each. Do you really think Hayward would entertain my phone call? I don't even see a phone no. in the user manual.

[CarlD]

From Hayward-pools.com:

Contact Hayward Residential Pool

Contact us by phone:

(908) 355-7995 (U.S.)

Mon-Fri, 8 AM – 5 PM

Contact us by letter:

Hayward Pool Products
Attn: Technical Services
One Hayward Industrial Drive
Clemmons, NC 27102

[FRANCIS]

Really like this unit. What's the logic in an oversized pump causing the problem? Wouldn't it force DE thru the fingers ALL the time? Do not want to re-pipe system. Must figure out how to solve this issue. just spent beaucoup dollars repairing extensive pool wall damage from last winter's brutality.

[CarlD]

OK. It MAY NOT be that your pump is too big and you have another problem. But a too-big pump for the filter is ALWAYS bad, and always a potential source of damage to the filter, regardless of DE, sand or cartridge.

Again, I'm not a DE filter expert--I only know the general principles, so I cannot help with details of what might be wrong.

Unless you have metal pipes (and nobody has used that for a long time, PVC plumbing is very easy and very quick. I've replumbed my pool as I've changed things over the years many times...when I didn't like how the pump to filter flow worked, when we added a deck and moved the pump and filter about 15' (the tough part was re-routing the 240v wiring for the pump), and when I added the SWCG before the 2013 season (again, additional electrical work was the bear).

So PVC is easy to work with and TigerFlex, the flexible PVC, gives you even more options. PVC and/or TigerFlex, Schedule 40 fittings, cleaner, primer (or cleaner/primer), glue, and a hacksaw are all you need. Most of it, except the TigerFlex, are at Home Depot or Lowes. So I dry fit it all first, cutting my PVC to length. When I'm satisfied, I use the cleaner on the pipe and the fitting, then wipe on the primer, then the glue. Stick the pipe into the fitting, give it a 1/4 turn to where you want it and move on. Nothing to it.