Full Outlet Pressure for a day or two, and then...?

[CorporateDog]

Hey, everyone. I was hoping someone might be able to help me diagnose what's happening with my sand filter and pump.

My equipment:

• 27' Radiant Metric Above Ground Pool
• Hayward Power-Flo Matrix Pump (Model SP1593FP)
• Hayward Pro Series Sand Filter (Model S210T93S)

My problem:

The outlet from the filter to the pool starts out with a really strong flow of water. Then after a day or two at most, I find that the flow has weakened significantly. I don't see any large air bubbles gathering in the pump's hopper, and what I do to typically solve the issue is shut down the pump, turn the filter's multiport to 'Recirculate', turn the pump back on for a few seconds, shut it down again, turn back to 'Filter', and then restart the pump.

At this point I see air bubbles come out of the outlet, and the water flow is strong again... at least for another day or two.

Filter pressure seems to remain constant (just under 20 psi). The skimmer and pump hopper are both clear of debris.

The only other thing that I've seen this season is that when I shut the pump down, and turn the multiport to a different setting, I'm getting a lot more water coming out of the backflow port than I seem to remember. My local pool guy told me that's normal when I'm in the middle of changing settings on the port. However, when I turn to 'Recirculate', a lesser amount of water continue to flow from the backflow port for something under ten seconds or so.

I changed the sand this season, and inspected the o-rings and such on the multiport, and everything looked okay (no obvious breaks or tears).

Any ideas? Thanks in advance!
--Dave

 

[Major_in_MS]

Recirculate does not clean the sand. Reduced water flow through a sand filter is due to the sand filling up with organic material. Have you backwashed your sand filter? Also, check the filter basket in your pump and your skimmer baskets, both of which can cause reduced water flow when they need emptying.

Routine Pump/Filter Maintenance - Trouble Free Pool

Filter pressure seems to remain constant (just under 20 psi)

Does your pressure gauge return to zero when your pump is off? A pressure gauge that "remains constant" is probably not functioning properly and should be replaced. They are easy to replace and can be found at Lowes, Home Depot, ACE Hardware, etc. Just be sure to get a 0-30psi or 0-60psi model, the higher pressure ones are not appropriate for swimming pool pressures.