Filter Not Filtering

[gregoryagu]

My pool filter seems to have stopped filtering. Here is what has happened so far:

0. All is working normally, pool clean and clear.
1. Algae Bloom about 1 week ago.
2. Checked stabilizer level - was low.
3. Started the SLAM process, raising the Chlorine to about 15 PPM.
4. Started noticing the PSI which usually is about 8-12, is 5.
5. I clean filter, but it's barely dirty.
6. I check water flow, and water seems to be flowing through just fine. Circulation seems normal.
7. I check paper filter cartridge, but don't find any tears or issues.


I just checked pressure by hand where water comes out into the pool and it is far lower than normal.

Does this mean there is blockage in the pipes somewhere?

I don't understand what is occurring or what I should do.

 

[Texas Splash]

Hello and welcome to TFP! A reduction in water flow could point to some sort of restriction. If there was a restriction on the suction side (pool to pump) you would expect the pressure to drop. If the restriction was in or after the filter you would expect the pressure to spike. At the same time, there's a always a chance the gauge itself is simply bad. You might check to see if the needle goes to zero when you turn the system off. See if the needle behaves erratically. Also make sure your pool's water level is high enough.

For the SLAM you attempted, did you actually complete the SLAM as noted on the SLAM page (link below)? What test kit do you have (add to signature), and how long did you maintain that SLAM? You might consider posting those test results here for us and we can validate for you. Also, please update your signature with all of your pool and equipment info. It will help a lot in the future. Nice to have you with us.

 

[atttech-2]

Welcome to the forum

I have a few ideas for you to try, with an algae bloom the pressure on the filter should be higher not lower. The pressure gauge measures the pressure between the return side of the pump and the pre-filtered water. If pressure is lower the pump is not pushing as much water as it used to so your idea of a blockage could be correct and is likely on the suction side of the plumbing Check the skimmer basket make sure all is as it should be weir door is moving freely no visible blockages. If you have a diverter plate make sure it is open and free from debris, you could remove it all together as a test. Check the pump impeller to be sure nothing got stuck in there. lastly if you have one run fish tape down the suction line from the skimmer to the pump you can also try a hose. I am sure others will be along with some more ideas.

Edit: I type slow Pat beat me to the punch haha

 

[Jimrahbe]

Greg,

Welcome to TFP... a great place to find the answers to all your "Why am I always Under Pressure?" pool questions...

Reduced flow is generally linked to higher filter pressure, not lower, so that is odd...

Obviously, if you have a 2-speed or VS pump, it could just be running at a lower speed... but, I assume you have a single speed pump..

Is the pump basket full of water when running? Are you getting any air bubbles out of the returns? Do you have any valves between your pump and filter?

I would turn off the power, open the pump lid, and feel the impeller to see if anything is in there.. Most likely not, but you have to start somewhere.

Does the pump prime as always, or is it different now?

Is the water in the skimmer stable or does it get sucked to the bottom of the skimmer and then fill and then repeat??

Thanks for posting,

Jim R.

 

[gregoryagu]

Thank you all for Replies.

I have updated the signature with everything I could find. Let me know if I am missing anything.

I have checked the baskets and impellor for blockage, but found nothing.

Motor seems to run as usual. When turning on pump, the skimmer basket fills with water and appears to be operating normally. It does not fill and repeat.

The Pressure gauge seems to be operating normally. It drops to zero when off.

Maintaining shock level at 15 ppm. Testing twice a day. On third day.

Have not tried backwashing pipe with hose yet.

I agree with readings of pressure gauge that says that the pressure is low, but not zero. Just using my hand over the water outlets in the pool - it seems the volume is good, but the pressure is low. Like I can stop it by covering it, whereas before, that was not possible.

The flow is the same whether it comes through the usual skimmer, or through the outlet that the pool cleaner hose goes to (Not sure the name of that - is it called a diverter?)

There has been little to no debris in the pool, so it is unlikely that blockage entered the system, but will try backwashing with hose.