DE returning to pool

Dom

Active member
Mar 4, 2016
25
California
#1
Hello, i recently retired my Pentair 2000 which was a great filter with a Pentair FNS 60, upon adding DE i noticed some returning into the spa, which i understand can be normal initially. A few days later i was skimming the pool, which by the way was looking great, when the pump turned on and i noticed DE still returning to the spa, i noticed it does it every time the pump starts initially and it is not visible at the pool returns. Yesterday i took the filter apart, cleaned it, inspected all the grids, O-rings, manifold for anything obviously wrong and did not see anything wrong, i added DE and let it run for 12 hours. This morning the pump started up and I saw the cloud of DE in the spa again, though it did not look as much as before i took it apart (i think). Any insight would be appreciated. Oh! is it normal for DE to shoot out of air relief valve once the air has been discharged? When the water dries up on the ground there is a lot of DE and the water looks grey when it shoots out, my old filter did not do this.
 

Texas Splash

Mod Squad
TFP Expert
LifeTime Supporter
#2
Hello and welcome to TFP! :wave: Could it be that you over-charged your filter with too much DE? That's one indication. I would say perhaps a torn grid or damaged manifold, but you say you already inspected those. But either of those would be the main culprits unless I'm missing something in the DE world. :) . Great to have you with us.

Oh, and I almost forgot, ..... perhaps your multiport or plunger valve seal/gasket. Whichever one you have.
 

JoyfulNoise

TFP Expert
Platinum Supporter
May 23, 2015
14,522
Tucson, AZ
#3
Is the screen on the internal air bleed assembly intact, no holes or tears and coated with DE when you open up the filter?

Did you properly charge the DE? How did you add it, what is your method? Did you run your pump for 24 hours after recharging?

Yes, you can get DE shooting out the air bleed.
 

Dom

Active member
Mar 4, 2016
25
California
#4
Thanks for the replies! i put the recommended 6lbs. of DE, i have the backwash valve for the FNS filter, and the screen on the air bleed is intact and did have DE on it when i took it apart, i did 2lbs. of DE at a time mixed in a bucket with water and poured through a skimmer (3 buckets), i ran the filter for 12hrs. not 24 hrs.

When the pump starts i get that initial cloud in the spa and i dont see it coming out of the pool returns, although it probably is, but after 10 minutes the spa is clear and looks great.
 

JoyfulNoise

TFP Expert
Platinum Supporter
May 23, 2015
14,522
Tucson, AZ
#5
Ok. I usually mix the DE as you do and add to the skimmer with the pump running on high speed. I do that for 30mins then leave the pump running on normal speed for at least 24 hours. If I don't, then I get what you describe. There's just something about fresh, clean DE that doesn't like to stick to the grids. Like all filters, it needs a bit of gunk to hold it all together.
 

JoyfulNoise

TFP Expert
Platinum Supporter
May 23, 2015
14,522
Tucson, AZ
#7
Matt, Do i need to start all over or can i let it run for 24 hrs. since i just slapped it all back together yesterday?
Just leave it. In my experience what you're seeing will subside. When it happened to me, it took a week for the plumes of DE to stop coming out. Though I will say this, if you do see a plume it should only be for 30secs or so and then stop. You should not see continuos DE plume.
 

Dom

Active member
Mar 4, 2016
25
California
#8
i thought it would subside after 2 weeks also after i installed the new filter, thats why i took it apart yesterday. Yes i just have that plume that lasts for a few seconds, definitely not continuous. i will let it run till tomorrow morning and see what happens in the next several days. Thanks!
 

Dom

Active member
Mar 4, 2016
25
California
#9
Well its been 3 weeks and I am still getting that initial plume of DE when the pump starts up. I stopped by a local pool place and the guy said that my 1.5 hp pump needs to be changed to a 2.0 hp. something about not packing the DE well enough to the grids, my previous Pentair 2060 was doing just fine with same pump. Any truth in that? Another thing he mentioned is too many angles to the filter inflow. With my previous Pentair 2060 it only had 2 90's leading to the filter inflow, now with my Pentair FNS 60 there are 5 90's leading to the filter. Any truth in that? Frustration and confusion setting in!
 

JoyfulNoise

TFP Expert
Platinum Supporter
May 23, 2015
14,522
Tucson, AZ
#11
Ok. I'm no longer a road hazard.

Dom,

Do you have check valves in between the pump and filter to keep the water from backing up into the pump when it shuts off?

Also, check for a small air leak. About a week ago the high flow manual air valve on my filter developed a tiny hair-line crack at the threaded connection to the pressure gauge. This caused a nearly undetectable dribble of water that I only discovered because the pressure gauge stopped working. Well, when the pump would shut off, the water in the filter would drain down and leave an air space at the top. This allowed to DE up there to slough off and then, when the pump kicked on in the morning, I'd get air bubbles at the return and big plumes of DE into the pool. Once I replaced the valve, the filter works perfectly. A defective or obstructed check valve could also do the same thing, i.e., allow water to back flow through the pump and leave an air pocket in the filter.

You may need to break the filter down again and really check that everything is sealed up.

The stories you got at the pool store are bogus. Why on earth would a bigger pump make your filter work better?? Sounds to me like the pool store wanted to sell you a new pump + installation. Also, the number of elbows is inconsequential. Might add a little extra head loss but will have no bearing on the DE on the filter.
 

Dom

Active member
Mar 4, 2016
25
California
#12
Matt, Thanks for the reply! I do not have a check valve between pump and the filter, it did not have one before i put the FNS in. As far as air leaks i dont think i have any, i started the pump and immediately opened the air relief valve to see if there was air in the filter and water immediately shot out, i dont know if that is an accurate way of checking for air in the system, but makes some sense to me. The whole filter and air relief valve / pressure gauge are brand new, 2 months old. I thought the guy was just BSing! I am thinking of breaking it down again.
 

JoyfulNoise

TFP Expert
Platinum Supporter
May 23, 2015
14,522
Tucson, AZ
#14
Dom,

OK, that's good to know. If there was no check valve and the air relief shoots water out straight away, then your filter is holding the water level. I would certainly hope a 2 month old brand new filter would.

Let me ask you this - how does your WhisperFlo pump sound? Also, do you have a model number for that pump, I assume it's a single speed.

Yeah, I think you have to open it up again. Something seems like it's not seated correctly or there's a small tear or hole somewhere. Believe me, I have a DE filter, so I know what a pain and mess it can be to open them up and troubleshoot them. Let us know if you find anything.

Good luck,

Matt
 

Dom

Active member
Mar 4, 2016
25
California
#15
Matt, the pump sounds quiet and it is a single speed. Although i just discovered its only a 1hp, my previous pool guy switched it out last summer and told me we were going from 2hp-1.5hp. he said it was a good used one from one of his accounts. :confused: Why are pics upside down?
IMG_1672.jpg
 

JoyfulNoise

TFP Expert
Platinum Supporter
May 23, 2015
14,522
Tucson, AZ
#16
No idea why the pics are upside down. Unless your a TFP supporter your attachment limit is quite low. You can use a photo hosting service like Photobucket to attach pics.

Even upside down I can read the plate says the service factor (SF) is 1.65 which makes the motor a 1.5HP motor. It was apparently rebuilt at some point because that is not an OEM motor on the WhisperFlo wet-end. No worries as long as whoever rebuilt it used the correct impeller.

Neither here nor there really. If the pump is ok then I'm out of ideas. That pump should be more than sufficient to handle your filter's flow rate. All I can suggest is the filter tear down and inspection to look for something. You should not be having DE shoot out of your returns.