Become a TFP Supporter Pool Math Forum Rules Pool School
Page 1 of 2 12 LastLast
Results 1 to 20 of 23

Thread: Air Bubbles Coming from Return After Sand Filter Bleed

  1. Back To Top    #1

    Join Date
    Sep 2009
    Location
    Houston, TX
    Posts
    104

    Air Bubbles Coming from Return After Sand Filter Bleed

    I was messing around with my sand filter and opened the bleed valve. No real reason just messing with things. Well now that I've done this I have a ton of air coming out of my returns. Help...lol
    1) 15000 Gallons Gunite
    2) Sand
    3) In Ground
    4) Pentair Intelliflo VS
    5) SWG

  2. Back To Top    #2
    Mod Squad zea3's Avatar
    Join Date
    Jul 2009
    Location
    Houston, Texas
    Posts
    9,200

    Re: Air Bubbles Coming from Return After Sand Filter Bleed

    Is the air bleed open while the pump is running? You may need to do that to let out any trapped air.
    TFP Moderator
    Helpful links: TF Test Kits,TFP Pool School, PoolMath
    Vogue 21' round AG, Pentair 1 hp 2 speed pump, 36 sq ft DE filter, Hayward S180T 150# sand filter, Houston, Texas
    Love TFP? Become a
    TFP Supporter!

  3. Back To Top    #3

    Join Date
    Sep 2009
    Location
    Houston, TX
    Posts
    104

    Re: Air Bubbles Coming from Return After Sand Filter Bleed

    Seems to have cleared out. Not sure what the issue was but it took care of itself. Odd.
    1) 15000 Gallons Gunite
    2) Sand
    3) In Ground
    4) Pentair Intelliflo VS
    5) SWG

  4. Back To Top    #4
    solarboy's Avatar
    Join Date
    Aug 2010
    Location
    Europe
    Posts
    337

    Re: Air Bubbles Coming from Return After Sand Filter Bleed

    I've seen this before. I think it's large bubbles of air caught in the turbulance in the filter and pump that gradually disperse. Sometimes just turning the pump off and waiting a few minutes helps, or turning the pump off and bleeding the filter.
    Self built 5500 gallon bare concrete (temporarily) pool with limestone coping, Pentair Swimmey 1/2 HP pump, Triton sand filter with DE, Simpool peristaltic muriatic acid pump with pH sensor and Monarch SWG. Home made solar heater with Pentair Compool control panel and 3 way valve. 1 skimmer, 1 main drain, 2 returns, 2" plumbing, Hayward auto fill valve.

  5. Back To Top    #5
    mas985's Avatar
    Join Date
    May 2007
    Location
    Pleasanton, CA
    Posts
    11,487

    Re: Air Bubbles Coming from Return After Sand Filter Bleed

    zea3 touched on this but for a in ground pool where the filter is above the water line, when you open the bleed valve with the pump OFF, air will get sucked into the filter. The weight of the water pulls in the air. So when the pump is turned back on, the air will be purged out of the filter through the returns. To bleed air from the filter through the bleed valve, the pump must be ON.
    Mark
    Hydraulics 101; Pump Ed 101; Pump/Pool Spreadsheets; Pump Run Time Study; DIY Acid Dosing; DIY Cover Roller
    18'x36' 20k plaster, MaxFlo SP2303VSP, Aqualogic PS8 SWCG, 420 sq-ft Cartridge, Solar, 6 jet spa, 1 HP jet pump, 400k BTU NG Heater

  6. Back To Top    #6
    solarboy's Avatar
    Join Date
    Aug 2010
    Location
    Europe
    Posts
    337

    Re: Air Bubbles Coming from Return After Sand Filter Bleed

    Is the pump below the water line then? I have had below the water line filters that have bled better with the pump off. I've similarly primed pumps by turning them on then off again when pockets of air have been trapped and simply running the pump was insufficient.
    Self built 5500 gallon bare concrete (temporarily) pool with limestone coping, Pentair Swimmey 1/2 HP pump, Triton sand filter with DE, Simpool peristaltic muriatic acid pump with pH sensor and Monarch SWG. Home made solar heater with Pentair Compool control panel and 3 way valve. 1 skimmer, 1 main drain, 2 returns, 2" plumbing, Hayward auto fill valve.

  7. Back To Top    #7
    mas985's Avatar
    Join Date
    May 2007
    Location
    Pleasanton, CA
    Posts
    11,487

    Re: Air Bubbles Coming from Return After Sand Filter Bleed

    The OPs pool is an in-ground and most of the time the equipment is above the water line so air will be sucked in when the valve is opened with the pump off. However, for above grounds and a few in-grounds where the water line is above the filter, you can purge the air with the pump off.
    Mark
    Hydraulics 101; Pump Ed 101; Pump/Pool Spreadsheets; Pump Run Time Study; DIY Acid Dosing; DIY Cover Roller
    18'x36' 20k plaster, MaxFlo SP2303VSP, Aqualogic PS8 SWCG, 420 sq-ft Cartridge, Solar, 6 jet spa, 1 HP jet pump, 400k BTU NG Heater

  8. Back To Top    #8

    Join Date
    Sep 2009
    Location
    Houston, TX
    Posts
    104

    Re: Air Bubbles Coming from Return After Sand Filter Bleed

    Water line is below the filter. Right on. Even leaving the bleed valve opened with the pump running though didn't seem to rid the system of air. Just gradually went away as I let the pump run.
    1) 15000 Gallons Gunite
    2) Sand
    3) In Ground
    4) Pentair Intelliflo VS
    5) SWG

  9. Back To Top    #9
    mas985's Avatar
    Join Date
    May 2007
    Location
    Pleasanton, CA
    Posts
    11,487

    Re: Air Bubbles Coming from Return After Sand Filter Bleed

    If you keep getting air into the filter when the pump is shut OFF (listen for the air bubbles in the filter), then it could be a gasket leak in the backwash valve that only lets in air but does not let out water when the pump is running.
    Mark
    Hydraulics 101; Pump Ed 101; Pump/Pool Spreadsheets; Pump Run Time Study; DIY Acid Dosing; DIY Cover Roller
    18'x36' 20k plaster, MaxFlo SP2303VSP, Aqualogic PS8 SWCG, 420 sq-ft Cartridge, Solar, 6 jet spa, 1 HP jet pump, 400k BTU NG Heater

  10. Back To Top    #10

    Join Date
    Sep 2009
    Location
    Houston, TX
    Posts
    104

    Re: Air Bubbles Coming from Return After Sand Filter Bleed

    I commonly hear what sounds like air in the filter. I've been concerned with my gasket because one time (yes I seem to like to make the mistake first and then learn) I moved the valve when the pump was on. Any other way to verify this may be faulty?
    1) 15000 Gallons Gunite
    2) Sand
    3) In Ground
    4) Pentair Intelliflo VS
    5) SWG

  11. Back To Top    #11
    mas985's Avatar
    Join Date
    May 2007
    Location
    Pleasanton, CA
    Posts
    11,487

    Re: Air Bubbles Coming from Return After Sand Filter Bleed

    When the pump is off and all is quite, listen to the filter. Does it sound like bubbles are rising?
    Mark
    Hydraulics 101; Pump Ed 101; Pump/Pool Spreadsheets; Pump Run Time Study; DIY Acid Dosing; DIY Cover Roller
    18'x36' 20k plaster, MaxFlo SP2303VSP, Aqualogic PS8 SWCG, 420 sq-ft Cartridge, Solar, 6 jet spa, 1 HP jet pump, 400k BTU NG Heater

  12. Back To Top    #12

    Join Date
    Sep 2009
    Location
    Houston, TX
    Posts
    104

    Re: Air Bubbles Coming from Return After Sand Filter Bleed

    Nevermind....I misread your post. It's when the pump is running. Maybe sounds like air...maybe like water flowing quickly through the valve.
    1) 15000 Gallons Gunite
    2) Sand
    3) In Ground
    4) Pentair Intelliflo VS
    5) SWG

  13. Back To Top    #13
    mas985's Avatar
    Join Date
    May 2007
    Location
    Pleasanton, CA
    Posts
    11,487

    Re: Air Bubbles Coming from Return After Sand Filter Bleed

    When the pump is running, air would not enter through the filter but it could on the suction side. Do you see bubbles in the pump basket?
    Mark
    Hydraulics 101; Pump Ed 101; Pump/Pool Spreadsheets; Pump Run Time Study; DIY Acid Dosing; DIY Cover Roller
    18'x36' 20k plaster, MaxFlo SP2303VSP, Aqualogic PS8 SWCG, 420 sq-ft Cartridge, Solar, 6 jet spa, 1 HP jet pump, 400k BTU NG Heater

  14. Back To Top    #14

    Join Date
    Sep 2009
    Location
    Houston, TX
    Posts
    104

    Re: Air Bubbles Coming from Return After Sand Filter Bleed

    I do...posted about that in a different thread. I love creating problems lol. I feel bad posting problems all the time. Conclusion of that thread was most likely an oversized pump

    bubbles-in-pump-strainer-basket-t26307.html
    1) 15000 Gallons Gunite
    2) Sand
    3) In Ground
    4) Pentair Intelliflo VS
    5) SWG

  15. Back To Top    #15
    mas985's Avatar
    Join Date
    May 2007
    Location
    Pleasanton, CA
    Posts
    11,487

    Re: Air Bubbles Coming from Return After Sand Filter Bleed

    The pump is probably sucking in air and passing it through to the filter although this should be fairly constant and not diminish over time.

    Do you have all of the valves open for the skimmers and main drain?

    A quick fix for the oversized pump problem would be to swap out the impeller for a smaller one. I replaced my impeller for a 1 HP Northstar down to a 1/2 HP version and cut my power consumption nearly in half.
    Mark
    Hydraulics 101; Pump Ed 101; Pump/Pool Spreadsheets; Pump Run Time Study; DIY Acid Dosing; DIY Cover Roller
    18'x36' 20k plaster, MaxFlo SP2303VSP, Aqualogic PS8 SWCG, 420 sq-ft Cartridge, Solar, 6 jet spa, 1 HP jet pump, 400k BTU NG Heater

  16. Back To Top    #16

    Join Date
    Sep 2009
    Location
    Houston, TX
    Posts
    104

    Re: Air Bubbles Coming from Return After Sand Filter Bleed

    All valves are fully open to both skimmer and the main drain. The noise is consistent. Air bubbles at the returns is minimal. What I was commenting towards at the start of this thread was a much higher rate of bubbles in the return flow. That has since diminished since the pump has been running. The constant flow of very light bubbles is still there. I would swap out my impeller but I'm still a bit concerned that I will lose too much flow to provide enough pressure to my mist cooler and to my spa jet returns when being used.
    1) 15000 Gallons Gunite
    2) Sand
    3) In Ground
    4) Pentair Intelliflo VS
    5) SWG

  17. Back To Top    #17
    mas985's Avatar
    Join Date
    May 2007
    Location
    Pleasanton, CA
    Posts
    11,487

    Re: Air Bubbles Coming from Return After Sand Filter Bleed

    It looks like you have a second pump for the spa, no? And I would suspect the misters don't require much in the way of flow rate.

    Also, the small bubbles are probably due to the SWG.
    Mark
    Hydraulics 101; Pump Ed 101; Pump/Pool Spreadsheets; Pump Run Time Study; DIY Acid Dosing; DIY Cover Roller
    18'x36' 20k plaster, MaxFlo SP2303VSP, Aqualogic PS8 SWCG, 420 sq-ft Cartridge, Solar, 6 jet spa, 1 HP jet pump, 400k BTU NG Heater

  18. Back To Top    #18

    Join Date
    Sep 2009
    Location
    Houston, TX
    Posts
    104

    Re: Air Bubbles Coming from Return After Sand Filter Bleed

    They actually ran the second pump for the waterfall feature. The misters do have to overcome a good bit of head pressure as they rise out of the water about 1 foot before the water comes out in a mist. I actually have to block off two returns to get adequate flow out of the misters.
    1) 15000 Gallons Gunite
    2) Sand
    3) In Ground
    4) Pentair Intelliflo VS
    5) SWG

  19. Back To Top    #19
    mas985's Avatar
    Join Date
    May 2007
    Location
    Pleasanton, CA
    Posts
    11,487

    Re: Air Bubbles Coming from Return After Sand Filter Bleed

    Then in that case, a two speed motor might be the ticket. You can run on low for circulation and high when you need it.
    Mark
    Hydraulics 101; Pump Ed 101; Pump/Pool Spreadsheets; Pump Run Time Study; DIY Acid Dosing; DIY Cover Roller
    18'x36' 20k plaster, MaxFlo SP2303VSP, Aqualogic PS8 SWCG, 420 sq-ft Cartridge, Solar, 6 jet spa, 1 HP jet pump, 400k BTU NG Heater

  20. Back To Top    #20

    Join Date
    Sep 2009
    Location
    Houston, TX
    Posts
    104

    Re: Air Bubbles Coming from Return After Sand Filter Bleed

    I've thought that may be the solution but I'm concerned I would just always be running it on high anyways (at least in the summer when I use the mist coolers which can last nearly 6 months in Houston). There's a few different scenarios for myself where the requirements for flow would be different
    1. Most common: Pump running in pool mode with with spa spillover, misters in place, some flow returning to spa to circulate.
    2. Pump running in pool mode with spa spillover, no misters, some flow returning to spa to circulate
    3. Pump running in spa mode, all water to spa
    4. In either of the first two cases my pool cleaner could be running as well. I'm not sure this matters as it runs off the booster pump.

    I'm kind of stuck between having a pump that's over sized for my piping (1.5 inch) which seems to be causing a very turbulent environment in my pump strainer basket and not to mention the cost, or the other scenario of purchasing a smaller pump and possibly running in to not having enough head to properly operate the misters (which I love because it's so **** hot here anyways lol)
    1) 15000 Gallons Gunite
    2) Sand
    3) In Ground
    4) Pentair Intelliflo VS
    5) SWG

Page 1 of 2 12 LastLast

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •