New filter/pump.yet still a quick pressure rise, slower flow

[UVM73]

I have in ground 16x32 that works just fine. (Hayward DE, 1.5 super-pump hp, grid system) Any issues over the last 20yrs I've solved quite well (mechanics, equipment, chemistry) so I have experience but now I'm trying to help my sister-in-law with an above ground pool,( not sure of the size..possibly 14x28 oval as a guess)
Last year she had continual problems with a new filter and pump (Hayward EC40DE/ 1HP power matrix I believe) Seems that pressure would double very quickly ( 10-15 minutes, even after bumping, and even after backwashing)
Because she did not bring the system in for the winter or drain it properly she cracked lots of components, both filter and basket housing. Rather than spend quite a bit on multiple part replacements I purchased a new system last week and installed it today. (Hayward EC50 with the larger 1.5 pump. (Overkill I know)
The extra power was impressive, but much like last year the pressure jumped rapidly after 10-15 minute upon INITIAL use. Bumping returns good pressure but only for 10 minutes. Since this was the FIRST use of a new pump/filter, I can't believe that the filter could be clogged so rapidly. The pool does have lots of suspended particles and algea since this is really the "startup" for the season. (Pool was also shocked heavily)
#1 Do you think that possibly too much DE was used for the initial coating? ( Maybe she did that last year too?) ( I used only 4 full scoops this year for a 24 SQ' area). I was thinking of backwashing and adding less DE to see if that helps, but I certainly want to make sure the elements are covered.)
OR.. #2...Filter is real dirty (that quick?) (Hard to imagine since the brand new/pump filter only ran for about 15 minutes and vacuuming has not been done yet, so any bottom residue has not been sucked up yet)
The fact that the quick pressure rise happened with both filters (last year and this) has me baffled. Being an above ground system theres no piping/plumbing to check other than the two short hoses leading in and out of the filter/pump. And since the flow is very good for that first 15 minute those hoses can't be the issue.
Any thoughts? Too much DE? Dirty filter that quick? Something else?..thanks

 

[JohnT]

If the water has suspended particles and algae, it would be normal for the filter to clog very, very quickly.

Run on recirculate and vacuum to waste to get it as clear as possible.

 

[zea3]

Are there cut off valves installed in the plumbing? If so are they in good condition? It almost sounds like a partial blockage in the line, like maybe from a broken valve, or a piece of debris getting blown into a bend in the pipe. Is the flow coming from the return reduced when the pressure rises? Maybe try unscrewing the eyeball from the return and see if anything is in there.

I am assuming you are using a DE scoop to measure the DE. The EC 50 calls for 5 scoops of DE, so that should not be the problem. It is possible if the pool is a black slimy swamp that algae could coat the elements and restrict flow through the filter, but usually doesn't happen within the first 15 minutes.

Also if the plumbing to and from the filter is flex tubing and not rigid pipe you will need to check and make sure the flex tubing is not collapsing on itself while the pump is running.

 

[UVM73]

Short cycles persist, followup to July 10 post re:filter

Topics merged by Moderator

For background please read my post of July 10..new pump, new filter. (10-15 minute cycles of an EC50 DE/1.5 HP (new) before flow slows to a crawl etc etc.
Since July 10th pool condition has improved but filter performance but ridiculously short cycles presist. I've even removed the backwash plug, forced a stream of water up into the tank to do a much more through cleaning on multiple occasions and 15 minutes later pressure doubles, return flow crawls. While the pool water is still hazy I wouldn't consider the condition to be such that its clogging the filter in 15 minutes.
I've noticed that when I open the air valve relief (actually I can remove it during operation) NO water spurts out even when the pump is running. I can see the water at the top however. The only time water comes out is after a complete backwash from below and then a restart.
I'm seriously thinking of removing the of the filter to get at the tubes manually for cleaning, but I hesitate to do this because the filter is brand new and I don't want any seal/leak issues when I reassemble. I would remove the assembly only for a complete rinsing, not an acid wash because the assembly/filter is all brand new.
I am also considering replacing the flexible return tube with rigid pipe, even though I can see no constriction or collapsing of the present lines. ( which are short by the way..maybe 4'). I'm grasping at straws trying every possible alternative and still looking for input from moderators and members. Help!

 

[duraleigh]

UVM,

Welcome to the forum. Reread JohnT's post. Your filter is doing exactly what is supposed to do. It is filtering things from your water.....so much so that it is quickly plugging up.

You have a water quality issue....not a filtering issue. My bet is if you post a set of test results without adding anything to the pool prior) you will be low on FC.

I will be very surprised, shocked, in fact, if your pool does not need to be shocked. :-D :-D