No jet flow or filter suction yet no change in pressure gauge

Renloos

Member
Jun 25, 2019
19
Ohio
Hello! First the backstory...

We installed our above ground 13500 gallon pool last year. (Found TFP right away so have been following this method all along). About the second month it was open, we started to lose jet flow and notice the water in the pump filter basket was about half full. We made sure there were no clogs and the filter basket was empty. We didn't notice any obvious leaks from the pool filter or hose going into the motor. We did notice a small drip from the gate valve. Once the clear lid was was opened and the basket refilled with water, jet flow would return for a short time (about 6 hours). We were never able to completely rectify the issue before it was time to close the pool down.

We just opened our pool 3 days ago. DE Filter was completely clean, connections tightened, no clogs, etc. After 1 day of running the filter, we again have a half filled pump filter basket and very low jet pressure. The pressure gauge on the filter running on low speed still reads 2 psi (no change). It runs at 10 psi on high speed. The air relief valve has a steady stream of water so there is no air in the filter.

Since I had started the SLAM process the day before and thought we might have clogged filter, we went ahead and shut everything down and opened up the filter to clean it. See photo 1.dirty filter1.jpg Obviously, there is junk on there but most of the DE was in clumps at the bottom (we use the slurry method for adding DE). dirtyfilter2.jpgDE clump bottom of filter.jpg Once everything was cleaned and reinstalled, jet flow and pool filter suction was great (pressure gauge remained at 2psi low speed and 10psi high speed). I went ahead and vacuumed the pool (some junk on the pool bottom but not bad at all) and started adding CYA. Overnight, we lost most jet flow and filter suction again and once again, the pump filter basket was only half full of water.

I'm guessing since I vacuumed yesterday, my filter might be clogged again...

So, here are my questions.
1. Why doesn't my pressure gauge increase if the filter is clogged?
2. Do I need to completely take the filter apart and hose it down every time or will a backflush be sufficient? It's very frustrating to have regular jet flow pressure for about 6 hours before it drops again. I do not have a bump filter.
3. Would a clogged filter cause air to enter the system and lead to air in my pump filter basket? Or should I be looking for an air leak?

Do I have two issue going on here at the same time causing my problems?
Thanks for your help once again!
 

Mdragger88

Well-known member
Jun 1, 2018
631
Hernando, Ms
De filters clog fast with algae! You’ll need to backwash alot during SLAM Process
You could start by replacing the pressure gauge- that would eliminate that unknown & if it’s good then u have a spare. They’re not expensive- tftestkits.net has good ones for $15.
if those 2 things don’t help definitely search for a leak
 
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Renloos

Member
Jun 25, 2019
19
Ohio
De filters clog fast with algae! You’ll need to backwash alot during SLAM Process
You could start by replacing the pressure gauge- that would eliminate that unknown & if it’s good then u have a spare. They’re not expensive- tftestkits.net has good ones for $15.
if those 2 things don’t help definitely search for a leak
Ok thanks for that info. Good to know I need to backflush often. We replaced the gate valve where we saw the original drips. We actually found cracks in the housing near the valve knob. We'll know in the morning if that was the issue. We'll look into trying a new gauge as well.