Become a TFP Supporter Pool Math Forum Rules Pool School
Results 1 to 5 of 5

Thread: Is a super low GPM pump better than a higher one?

  1. Back To Top    #1

    Join Date
    Mar 2012
    Location
    Maryland
    Posts
    87

    Is a super low GPM pump better than a higher one?

    So here's the deal, I got a new filter (filter details in signature). When I installed the new filter coincidentally my pool pump blew (posted a thread about this a while back). So while I ordered a new pump I placed a shallow well pump (3/4 hp) 9.2 gpm pump as a substitute. This pump was sooo low power that it didn't even register PSI on my filter gauge. It took around a week until the pump came in, but I noticed my pool water was crystal clear. I mean so clear you could spot some imperfections within the liner.

    I then got my motor (1hp 60gpm) and installed this. Right when I powered the pump up I noticed a cloudy mess shot out from the discharge line. It was like a cloudy discharge that came from the filter. The water overall got a little cloudy (but not too much). The gauge was registering around 10PSI.

    So my theory is in a low power pump the water moves very slow through the sand and filters better. But in a high powered pump it goes through so fast that it can even take material with it out the filter? The filter is in great condition I put new sand and the laterals were perfect. What causes these anomalies!!!!!
    13,500 gallon above ground round pool. Vinyl Liner. Hayward S244T 3.1 cu ft sand filter. Hayward Powerflo 1HP pump (single speed induction). HTH 6-way test kit.

  2. Back To Top    #2
    Mod Squad jblizzle's Avatar
    Join Date
    May 2010
    Location
    Tucson, AZ
    Posts
    37,389

    Re: Is a super low GPM pump better than a higher one?

    Certainly lower flow filters better, that is one advantage of the 2 speed and VS pumps. The other is lower running costs.

    But, you still need to have enough flow for adequate circulation of chemicals and under 10gpm might be pushing it. That is also too low for my SWG flow switch. So there is a trade off.
    Jason, TFP Moderator
    18k IG pebblesheen pool, Hayward ProLogic P4 w/ T-15 SWG, Pentair 1HP 2-speed Superflo, Hayward 6020 DE filter
    500 sqft Heliocol solar panels, ThePoolCleaner, TF-100 test kit w/ SpeedStir
    Pool School + Test Kit + PoolMath = A TROUBLE FREE POOL
    If you found TFP helpful and we saved you money ... Become a TFP Supporter!

  3. Back To Top    #3

    Join Date
    Mar 2012
    Location
    Maryland
    Posts
    87

    Re: Is a super low GPM pump better than a higher one?

    Quote Originally Posted by jblizzle View Post
    Certainly lower flow filters better, that is one advantage of the 2 speed and VS pumps. The other is lower running costs.

    But, you still need to have enough flow for adequate circulation of chemicals and under 10gpm might be pushing it. That is also too low for my SWG flow switch. So there is a trade off.
    OK,

    If that is the case. Is there some sort of "Variable Resister" I can splice between my pump so that I can "slow" the pump down a little? I'm thinking some of those Light dimmers.
    13,500 gallon above ground round pool. Vinyl Liner. Hayward S244T 3.1 cu ft sand filter. Hayward Powerflo 1HP pump (single speed induction). HTH 6-way test kit.

  4. Back To Top    #4
    JasonLion's Avatar
    Join Date
    May 2007
    Location
    Silver Spring, MD
    Posts
    37,879

    Re: Is a super low GPM pump better than a higher one?

    Not really. There are motor speed controllers, but they require special "inverter rated" motors.
    19K gal, vinyl, 1/2 HP WhisperFlo pump, 200 sqft cartridge filter, AutoPilot Digital SWG, Dolphin Dynamic cleaning robot
    Creator of PoolMath and Pool Calculator. Other handy links: Support this site, TF Test Kits, Pool School

  5. Back To Top    #5
    happyheathen's Avatar
    Join Date
    Aug 2012
    Location
    Sacramento CA
    Posts
    225

    Re: Is a super low GPM pump better than a higher one?

    I have seen 2 motor controllers in my life - both rated for fractional hp only (exhaust fan in kitchen, and a cute little box you plugged you old drill into, and, presto! you now have one of the fancy variable speed drills. Yes, the was circa 1960.

    I wouldn't even think about trying it with a multi-hp pool motor, even one rated for it - too much current.
    Dave
    Sacramento
    1980's 15,000 Gal IG Plaster; 1 1/2 hp Hayward Northstar; Hayward Swimclear C3025 Cartridge Filter (325 sq ft, nom.); Pentair Legend; Polaris PB4-60; Equipment 40' from pool. p.s.: it's an aye-aye.

Posting Permissions

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