Do Tagalus filters fail (structurally) very often?

[RRpoolowner]

I was helping a girlfriend with her "new" house with some old equipment on it.. her poolsweep was rather lethargic so I adjusted her "three way" discharge valve to divert more pressure to her pool sweep supply pipe by throttling the flow to the three "oversized" supplys on the side of the pool. The problem also is/was that the pressure gauge was shot, it was half full of water/no needle on it so one of the things we did was to buy a new one, but tooo late, I guess...

Well, as we were gone to the pool store (bought a new gauge) the Darn Tagelus filter blew out the side, basically structural failure. She seemed to get very upset and all went down hill after the failure. The test pressure shown is 50 psi (115' of head) on the filter housing . I'm feeling there's no way in **** that the pressure ever got up that high. As I recall, the pump is a 1 hp, but I don't have the model/etc. to check pump head curves/etc. I'm a mechanical engineer, retired, and had a pool for over 25 years, and understand hydraulics.

My question is this.

Do you find that Tagelus have a high rate of structural failure, even at much lower pressures? the housing is black/blown type of 'fglass and looks like it's about 1/8" thick. looks like some of the f'glass is actually exposed/flaking. Does sun exposure degrade the integrity of the shell?

Thanks in advance.

 

[spishex]

Here's my response to your other post:

The Tagelus and Triton models make up probably 90% of the fiberglass sand filters around here, so all the structural failures I see are with these models but that's not necessarily because of the filters themselves.

You're right, the pump was not likely to apply 50psi, but UV light degrades fiberglass over time once the outer varnish or paint wears through (sounds like the case with your filter since you can see some of the threads). The odds of a break are obviously increased if it's mishandled or abused. For instance: moving it with sand in it, tipping over the tank to get the sand out, accidentally thwacking it with a 4x4 while you're building a roof over it, etc.

How big is the crack? I never thought it would work but I have a customer who patched a 4 inch crack in a Tagelus tank from the outside and it held, so you might give it a shot. As I mentioned in the other post it's not something I'd ever do as a service call (except in that one particular instance) but I've seen it work too many times to say you shouldn't try it yourself.