Help With Back Pressure and Debris in Pump Strainer Basket

ehuesman

Active member
Mar 16, 2014
27
0
California
#1
Hi All,

I was doing doing my pool routine tonight, and I noticed while the pump was running there was a large ball of debris in the pump's strainer basket. The debris was pressed up against the side of the basket and blocking the pump's outlet, but as soon as I turned the pump off, the debris got sucked back into the suction line. The pump lid isn't crystal clear anymore, so I can't be 100% sure, but it looks like the debris is just normal leaves and "strings" from the palms.

I have a couple of questions:

1. Since I haven't had a lot of debris in the pool so far (I've only owned it for 9 months, so I haven't had the pleasure of a fall season yet), it is entirely possible this back pressure has always existed and I just never noticed it before. Is it normal to have back pressure at the pump? If it is not normal, is it harmful, what causes it? I bought new cartridges for the filter in about April, and the pool was barely used over the summer, so I can't imagine the cartridges are clogged.

2. Regardless of whether the back pressure is normal, how do I at least temporarily stop it so I can clear out the debris?

Thanks in advance for your assistance!

- Eric
 

kimkats

Mod Squad
LifeTime Supporter
Jul 11, 2012
35,421
0
Tallahassee, FL
#2
If I am reading this right what you are saying is that when your pump is running you can see stuff in the basket that sits right in front of you pump. When the pump is turned off the stuff goes back into the pipe it came from (the pipe that comes from the pool skimmer).

When I see stuff in my pump basket area that did not come out with the basket I just open the valve just before it and let the water overfill the basket holder and flush it out.

I do not have the problem of the stuff getting sucked back into the pipe BUT I have an AGP so...........

I hope this helps.

Kim
 

pooladdict

In The Industry
TFP Guide
May 15, 2007
819
0
New Brunswick Canada
#3
It's entirely possible it was always there. Debris in your pump basket also shows that is it getting past your skimmer(s) basket as well. You need to clean those more often and check to see if they are in working order and properly seated.
 

timerguy

Well-known member
Oct 26, 2013
1,141
0
71
Chapin, SC
#4
I try to clean out my skimmer baskets when the pump isn't running, but once in a while I've cleaned them while the pump is running. As a result, a few leaves made their way to the pump basket. I remove them quickly after I notice them, but they have never gone back to the pool (at least that I know of). I have noticed a time or two that a skimmer basket will float. I guess that could be a cause too. Seen that I could put a weight in them to keep them from floating. But, again, I've only seen that twice in the last three swimming seasons I've been here.
 

duraleigh

Admin
Mod Squad
LifeTime Supporter
Platinum Supporter
TFP Expert
In The Industry
Apr 1, 2007
31,263
3
Sebring, Florida
tftestkits.net
#5
There is no back pressure in a circulatory system unless you are sucking in air.

If you suck in air (through a suction side leak), the air will pressurize in the filter and when the pump is turned off, that pressure from the air accumulated in the top of the filter pushes water backwards.

The solution is to find and fix that suction side leak. There is an article in Pool School that may help.
 

prs

LifeTime Supporter
Silver Supporter
Sep 9, 2014
155
0
Bakersfield, CA
#6
If you can't fix the suction side leak right now then a short term solution might be to bleed the air out of your filter before turning off the pump (you will likely find a bleed valve at the pressure guage).

Alternatively you could close all the valves on the suction side of the pump and then immediately turn off the pump (and I mean immediately...pumps don't like being run dry).
 

pooladdict

In The Industry
TFP Guide
May 15, 2007
819
0
New Brunswick Canada
#7
I do know, if your have loose fittings at the filter and the pump is shut off, the water will gurgle back down that line. I believe the back pressure is caused by the water in the filter being higher then the pump. Trust me, I know, happened to me and I had to freaking prime the pump all over again every time the timer shut it off. Once that fitting was tightened, I could turn pump off and the water level wouldn't change in the basket area.
 

duraleigh

Admin
Mod Squad
LifeTime Supporter
Platinum Supporter
TFP Expert
In The Industry
Apr 1, 2007
31,263
3
Sebring, Florida
tftestkits.net
#8
I do know, if your have loose fittings at the filter and the pump is shut off, the water will gurgle back down that line. I believe the back pressure is caused by the water in the filter being higher then the pump.
That can certainly be true but OP describes the "backpressure" as a rather sudden event, which is most always from air in the filter decompressing. A leak on the pressure side of the system with the pump off would more likely be a slow event.

Additionally, a loose fitting after the pump usually results in a water leak (pump on) which is usually pretty easy to notice.
 

MarianParoo

Well-known member
Aug 16, 2014
4,615
0
Northern IL
#9
This doesn't solve your issues, but you also might want to use skimmer socks to reduce the gunk making its way to your pump basket. They work a treat.
 

ehuesman

Active member
Mar 16, 2014
27
0
California
#10
Thanks to all for your input and replies. In regards to debris being in the basket in the first place, it is from my suction-side cleaner (Poolvernuegen).

I was thinking the back pressure could be created by a suction-side air leak, like Duraleigh describes, but there is no air visible in the pump basket after it primes. Would I always expect to see air bubbles in there if there was a leak?

I do get gurgling, and the water lowers, but only if I take the lid to the pump off. If I'm just turning the pump off, then the water level stays the same and there is no gurgling, just the effect of the back pressure that I described in my original post.

My pump and filter are above the pool level if that matters in any of this.

Thanks again for any insight.