Losing pressure

[susanfromMa]

24' AG round.
When filter is initially turned on the return pressure in pool is fabulous. Shortly after it loses it's punch.
Gauge says still 12-15 psi. But definitely not pushing water into pool at that. It moves water, but not strong.
I've tightened all connections. Siliconed the hose ends. I'm at a loss. Can't figure out where air is getting in. I'm guessing it's on the exit of filter if I believe pressure gauge.
Please help. I'm losing remaining sanity.?
I don't want to burn out motor.

 

[mknauss]

What you describe typically implies algae in the water.
Can you post a full set of test results? How does the water look?

Please fill out a signature as it helps us help you.

 

[susanfromMa]

Algae? Hmm. Been slowly working on getting pool ready for season. I've been vacuuming mainly on waste.
Didn't run chemistry yet. Was more concerned with lack of pressure. Chlorine has been added.

 

[mknauss]

What is your clean filter pressure?

 

[susanfromMa]

Hi. Pressure says 12-15. It does change when I turn filter off or try to vacuum. Am I answering what you are asking?

 

[mknauss]

Right after you clean your filter, what is the pressure it shows?

A signature listing your pool type, volume, equipment etc would be very helpful.

 

[susanfromMa]

24' AG round 48"
Haywood SP1580 PowerFlo lx 1Hp pool pump new 7-16

Just added that to signature

PSI stays steady between 12&15 PSI

 

[mknauss]

I moved the information to your Signature.
What filter type do you have? Sand, DE, Cartridge?

So after you clean the filter the pressure is 12 psi and when the pump flow lessens your filter pressure is 15 psi?

 

[susanfromMa]

Sand filter
The PSI holds fairly steady while the return to pool pressure lessens. I put my hand in pool and feel how hard the pressure it. When I turn filter on the flow is powerful, then it lessens, all while filter PSI stays same. I've tapped gauge, and it's stays.

 

[mknauss]

The primary cause of water flow reducing is the filter being clogged. Have you put any pool store potions (floc, clarifier,etc) into this pool and run it through the sand filter? Have you deep cleaned the sand filter since installing in 2016?

 

[susanfromMa]

Haven't added anything but chloride this season.
Filter is from 2001 and have not done anything special to it other than regular pool stuff.

 

[susanfromMa]

I did a really long backwash with fresh water into skimmer. The pressure into pool now seems to be holding steady and strong. Thank you. Hopefully issue is cleared.