Become a TFP Supporter Pool Math Forum Rules Pool School
Results 1 to 18 of 18

Thread: Do I need a variable speed pump?

  1. Back To Top    #1

    Join Date
    May 2011
    Location
    Coral Springs, FL (near Ft. Lauderdale)
    Posts
    92

    Do I need a variable speed pump?

    I'm doing some upgrades (SWCG, new lights) and the installer keeps telling me I should upgrade to a VS pump. I have a single speed 2 HP Hayward pump that works fine and am replacing the motor as it is getting loud (happens every 5-6 years). I have a simple pool with no water features and the pump runs a few hours a day to circulate and operate the Hayward Pool Vac. I did the math and it would take years to recoup the cost of the pump in electricity savings, not to mention that I don't even know when I would run the pump at anything less than full speed. Am I missing something?

    Thanks!
    15x30 inground concrete pool w/spa and spillover, all under screen enclosure
    Hayward C1200 StarClear Plus Cartridge Filter and Hayward Navigator V-Flex
    Jandy AquaPure 1400, Laars LX400 propane heater w/120 gal above-ground tank
    Jandy VS FloPro 2.7 HP Pump VSFHP270JEP; FlowVis FV-C Flow Meter
    Jandy iAquaLink and OneTouch controller w/PDA remotes; JVA for draining pool

  2. Back To Top    #2
    JoyfulNoise's Avatar
    Join Date
    May 2015
    Location
    Tucson, AZ
    Posts
    11,625

    Do I need a variable speed pump?

    A 2-speed would be a better option. Running a single speed, 2-HP pump just to circulate and filter water is a waste of electricity. A 2-speed on low would do the same thing for a lot less energy and you can use high speed for vacuuming.

    A VS pump would allow you to control the on/off times and pump speeds more precisely. A very low speed setting on a VS pump (say <1000RPM) uses about as much power as two, 100W light bulbs.
    Matt
    16k IG PebbleTec pool, 650gal spa, spillway and waterfall, 3HP IntelliFlo VS / 1.5HP WhisperFlo, Pentair QuadDE-100 filter, IC40 SWCG, MasterTemp 400k BTU/hr NG heater, KreepyKrauly suction-side cleaner Dolphin S300i robot, EasyTouch controls, city water, K-1001, K-2006 and K-1766 test kits, Mannitol test for borates

  3. Back To Top    #3

    TFP Guide

    chiefwej's Avatar
    Join Date
    Jun 2011
    Location
    Tucson
    Posts
    2,853

    Re: Do I need a variable speed pump?

    Quote Originally Posted by JoyfulNoise View Post
    A 2-speed would be a better option. Running a single speed, 2-HP pump just to circulate and filter water is a waste of electricity. A 2-speed on low would do the same thing for a lot less energy and you can use high speed for vacuuming.

    A VS pump would allow you to control the on/off times and pump speeds more precisely. A very low speed setting on a VS pump (say <1000RPM) uses about as much power as two, 100W light bulbs.
    Actually only ONE 100 watt bulb. My 3hp intelliflo use 100 watts @ 1,000rpm, 200 watts @ 1,500 rpm.

    However, I agree that a two speed would be a more economical choice for the OP. Just replace the motor with a two-speed one and save about 1/2 or even more on your power consumption. No need for a new pump, just a motor and rebuild kit.
    chiefwej
    Tucson, AZ
    16x36 rectangular (19k) Pebble Tec play pool/spa, Pentair Intelliflo VS 011018, Super II 2hp (spa), Aqua Rite T-15 SWG, Pro Grid 60 DE, Hayward H400 & Heliocol Solar heating, A&A infloor system, fill water w/high CH and TA, 50 ppm borates,TF-100 test kit

  4. Back To Top    #4
    Nectarologist's Avatar
    Join Date
    Apr 2015
    Location
    New York
    Posts
    362

    Re: Do I need a variable speed pump?

    Quote Originally Posted by HofstraJet View Post
    it would take years to recoup the cost of the pump in electricity savings,
    Thanks!
    That's says it all to me. I may be missing something too but I only hear about the cost savings. That issue has been decided for you. I was going to get a tankless water heater for my house when I did the math it too was years and years to recoup. If you were buying new maybe but to junk a working pump, I wouldn't.
    Inground, vinyl liner, 16 x 32 (approx. 21k gallons), roman end w/ bench, 2 Jandy LED lights
    Pump: Jandy Flopro, 1.5 hp Heater: Raypak, 266k btu (P-R266-A-EN-C; nat gas) Filter: Jandy C340 (cartridge filter) Robot: Doheny's Dolphin Discovery

  5. Back To Top    #5
    Mod Squad pooldv's Avatar
    Join Date
    Aug 2012
    Location
    DFW, TX
    Posts
    23,999

    Re: Do I need a variable speed pump?

    A 2 speed pump will pump about half the water for about a quarter of the electric cost. Low speed is usually plenty for normal filtering, skimming, making chlorine, etc.

    Like Chief I run my variable speed at 1100 rpm for skimming, filtering and making chlorine. It uses 150 watts and costs about 12 buvks a month to run my pump 24x7. We have lots of trees and often need continuous skimming.
    TFP Moderator
    If TFP helped you or saved you money - Become a TFP Supporter! <--Click here
    2012 build and pics, 20k gal gunite, black onyx pebblesheen, OK flagstone, IntellifoVS, cart filter w/Pleatco, IC40 SWG, Solartouch, 5 12'x4' solar panels, HP50HA heat pump, 8mil solar cover, borates, TF-100 test kit, SONOS, Doheny's Discovery Robot, hot tub on bleach

  6. Back To Top    #6

    Join Date
    May 2011
    Location
    Coral Springs, FL (near Ft. Lauderdale)
    Posts
    92

    Re: Do I need a variable speed pump?

    Thanks for the tips. A few questions:

    Can I just replace the motor in my pump with a 2 speed motor?

    Would a Jandy iAqualink recognize/be programmed for the two speed motor and allow me to control it accordingly?
    15x30 inground concrete pool w/spa and spillover, all under screen enclosure
    Hayward C1200 StarClear Plus Cartridge Filter and Hayward Navigator V-Flex
    Jandy AquaPure 1400, Laars LX400 propane heater w/120 gal above-ground tank
    Jandy VS FloPro 2.7 HP Pump VSFHP270JEP; FlowVis FV-C Flow Meter
    Jandy iAquaLink and OneTouch controller w/PDA remotes; JVA for draining pool

  7. Back To Top    #7
    JoyfulNoise's Avatar
    Join Date
    May 2015
    Location
    Tucson, AZ
    Posts
    11,625

    Re: Do I need a variable speed pump?

    Quote Originally Posted by HofstraJet View Post
    Thanks for the tips. A few questions:

    Can I just replace the motor in my pump with a 2 speed motor?

    Would a Jandy iAqualink recognize/be programmed for the two speed motor and allow me to control it accordingly?
    Yes you can replace the motor. Typically you get a new motor and a wet end rebuild kit as the impeller can be different for a two speed.

    As for controls, I don't know Jandy but I know that Pentair requires the installation of special relay to control a 2-speed. It's a simple add-on for Pentair, I don't know how Jandy does it. You can probably call their technical support and ask.


    Matt
    16k IG PebbleTec pool, 650gal spa, spillway and waterfall, 3HP IntelliFlo VS / 1.5HP WhisperFlo, Pentair QuadDE-100 filter, IC40 SWCG, MasterTemp 400k BTU/hr NG heater, KreepyKrauly suction-side cleaner Dolphin S300i robot, EasyTouch controls, city water, K-1001, K-2006 and K-1766 test kits, Mannitol test for borates

  8. Back To Top    #8
    JoyfulNoise's Avatar
    Join Date
    May 2015
    Location
    Tucson, AZ
    Posts
    11,625

    Re: Do I need a variable speed pump?

    Also, check with your electric utility. On some parts of the country, utilities will offer rebates to customers that switch to energy efficient pumps. If you can get a rebate, it might make a VSP financially attractive.


    Matt
    16k IG PebbleTec pool, 650gal spa, spillway and waterfall, 3HP IntelliFlo VS / 1.5HP WhisperFlo, Pentair QuadDE-100 filter, IC40 SWCG, MasterTemp 400k BTU/hr NG heater, KreepyKrauly suction-side cleaner Dolphin S300i robot, EasyTouch controls, city water, K-1001, K-2006 and K-1766 test kits, Mannitol test for borates

  9. Back To Top    #9
    Mod Squad pooldv's Avatar
    Join Date
    Aug 2012
    Location
    DFW, TX
    Posts
    23,999

    Re: Do I need a variable speed pump?

    Yes, you can just swap the motor to a 2 speed, be sure to match the impeller to the new motor. Other motors usually use a switch mounted to the end of the motor to switch from hi to lo.
    TFP Moderator
    If TFP helped you or saved you money - Become a TFP Supporter! <--Click here
    2012 build and pics, 20k gal gunite, black onyx pebblesheen, OK flagstone, IntellifoVS, cart filter w/Pleatco, IC40 SWG, Solartouch, 5 12'x4' solar panels, HP50HA heat pump, 8mil solar cover, borates, TF-100 test kit, SONOS, Doheny's Discovery Robot, hot tub on bleach

  10. Back To Top    #10
    jrs_diesel's Avatar
    Join Date
    Aug 2014
    Location
    League City, TX
    Posts
    215

    Re: Do I need a variable speed pump?

    I run a single speed 2 HP pump for 6 hours a day in the summer. Based on voltage and current (amps) readings, I found out that the pump costs me about $20 a month to operate. My A/C on the other hand, sucks down far more electricity in the summer

    I would like to replace my pump with a quieter and more effecient 2 speed pump, however I am patiently waiting my current one to break before I do that. I would also has to change out my Intermatic timer to run a two speed motor.

    A variable speed pump is nice, but I've decided against them for several reasons:

    Much more expensive than a 2 speed (even with changing out the timer).
    More sensitive to power surges/spikes and lightning due to the amount of electonics in the motor controller
    Most do not get along well with GFCI breakers

    If your in an area with power quality issues, or a lot of thunderstorms, I would favor the two speed pump over a variable speed pump.
    J.R.

    20K IG gunnite pool
    2HP Hayward single speed pump
    Cartridge filter

  11. Back To Top    #11

    TFP Guide

    chiefwej's Avatar
    Join Date
    Jun 2011
    Location
    Tucson
    Posts
    2,853

    Re: Do I need a variable speed pump?

    When I switched to a VS pump I also added two "whole house" type surge protectors. One at my main electrical service panel and a second smaller one at the pool sub-panel. Now all my household electronics have protection and my pool equipment has double protection. Total cost about $150.

    It was suggested that while the main panel provides primary protection for everything, the long wire run to the sub-panel can act like an antenna picking up lightning effect surges, hence the second one. We get a lot of lightning storms during Monsoon season.
    chiefwej
    Tucson, AZ
    16x36 rectangular (19k) Pebble Tec play pool/spa, Pentair Intelliflo VS 011018, Super II 2hp (spa), Aqua Rite T-15 SWG, Pro Grid 60 DE, Hayward H400 & Heliocol Solar heating, A&A infloor system, fill water w/high CH and TA, 50 ppm borates,TF-100 test kit

  12. Back To Top    #12
    Jaimslaw's Avatar
    Join Date
    Jun 2015
    Location
    San Diego, CA
    Posts
    299

    Re: Do I need a variable speed pump?

    Always thought how nice it would be if pool owners could temporarily and easily plumb in a demo VS or dual speed pump as a trial method of determing cost savings - but equally important IMO, how it performs with one's pool configuration (rooftop solar, suction side cleaners, spillways, waterfalls, etc - and various combinations of these).

    For pro dual speed pump reasons already articulated on this forum, probably will go that route (here in San Diego, required to go with one or the other).
    Pool: 13k gal. in-ground; Stonescape Mini Pebble - Tropics Blue; Connected Spa - dual spill-over; Aqua Rite T-15 SWCG; AquaLogic PS-4 Automation; Sta-Rite DE Filter; Sta-Rite Max-e-Therm 400k BTU pool heater; Intellifo 2-VST Pump; Stenner 45mp2(25psi/10gpd) acid injection; Bulbwizard color LED pool lights; Poolvergnuegen 2 wheel side suction cleaner; FAFCO rooftop solar. TF-100 w/ speed stir.

  13. Back To Top    #13
    jrs_diesel's Avatar
    Join Date
    Aug 2014
    Location
    League City, TX
    Posts
    215

    Re: Do I need a variable speed pump?

    The cost savings depends heavily on your electric rate, and a VS really helps if you have a high rate.

    My rate here is 9 a kilowatt hour which for my pump, a 2 HP single speed, only uses $20 a month running for 6 hours a day. It would take me a loooooonnng time to recoup the cost of a VS pump at that rate, which is why I'm in not particular hurry to replace my pump unless it breaks. And even then I'll be choosing a 2 speed over a VS since they are more rugged, will last longer, and is cheaper than a VS.
    J.R.

    20K IG gunnite pool
    2HP Hayward single speed pump
    Cartridge filter

  14. Back To Top    #14

    Join Date
    Nov 2015
    Location
    Ok ok
    Posts
    812

    Re: Do I need a variable speed pump?

    So after reading through this thread, my understanding is that you can't just simply replace a single speed for a two speed, it would require some type of control? I guess it would have to to know what speed to run at? Of all the things I've read about here I'm having the hardest trouble with electric motors. Right now I have three separate motors, all are simply either on or off. Good news is, for now they all work. I just want to learn what to do when the time comes.


    ~14K gallon - AquaRite AQR15 SWG - pool Newly plastered on April 9 2016
    TF100 kit - STA-RITE SYSTEM3 Modular Media Filtration - Model S8M150
    Pool water supply from on site water well = CH of ~350 and TA of ~350
    Doheny's Discovery Automatic Robotic Cleaner/Pentair Model 011018 VS Pump
    Sundance Altamar Hot tub separate from pool / central Oklahoma

  15. Back To Top    #15
    JoyfulNoise's Avatar
    Join Date
    May 2015
    Location
    Tucson, AZ
    Posts
    11,625

    Re: Do I need a variable speed pump?

    Quote Originally Posted by Lykly View Post
    So after reading through this thread, my understanding is that you can't just simply replace a single speed for a two speed, it would require some type of control? I guess it would have to to know what speed to run at? Of all the things I've read about here I'm having the hardest trouble with electric motors. Right now I have three separate motors, all are simply either on or off. Good news is, for now they all work. I just want to learn what to do when the time comes.


    Sent from my iPhone using Tapatalk
    Simple response is this -

    Single-speed pumps require a single source of electrical power. They are either 220V or 120V. The wire feeding them is a three conductor wire - hot (black), neutral (white) and ground (green). They can be controlled with either a simple mechanical timer (on/off switch) or relays on an automation panel.

    2-Speed pumps require two powered conductors. The wiring on a 2-speed is slightly different as it uses what's called a 3-wire supply which is actually 4 conductors in the wire - two hots (black & red), one neutral (white) and one ground (green). Switch on one hot line and you get half speed from the motor (1725 RPM); switch on the second powered conductor and you get full speed rotation (3450RPM). These motors can be controlled with mechanical timer switches that are designed for 2-speed pump operation OR from an automation panel, usually with a special relay designed for 2-speed pumps. Some 2-speed pumps come with an on-board "HI/LOW" switch to make things easier.

    Variable Speed pumps just need a single power supply (220V is pretty typical) and the conductor can be your standard 3 wires - hot, neutral and ground. The VSP's do all the speed control using on-board electronics. So many of them have a little 4 line LCD display on them with buttons that allow you to access all the features on the pump. These pumps can be run as stand-alone or with an automation panel. If they are run as part of an automation panel, there is usually two connections to make - power to supply the motor and a communications cable to run back to the automation panel (RS-485 or some other standard serial communication).

    So, if all you have right now is a single-speed pump and a mechanical timer, then in order to run a 2-speed you might have to have new wiring pulled if there is not enough power supplied. In this case, it might be easier to simply go with a VSP, ditch the mechanical timer and use the on-board electronics of the VSP to control pump run times. If you have an automation panel, then there's a lot more flexibility.
    Matt
    16k IG PebbleTec pool, 650gal spa, spillway and waterfall, 3HP IntelliFlo VS / 1.5HP WhisperFlo, Pentair QuadDE-100 filter, IC40 SWCG, MasterTemp 400k BTU/hr NG heater, KreepyKrauly suction-side cleaner Dolphin S300i robot, EasyTouch controls, city water, K-1001, K-2006 and K-1766 test kits, Mannitol test for borates

  16. Back To Top    #16

    TFP Guide

    chiefwej's Avatar
    Join Date
    Jun 2011
    Location
    Tucson
    Posts
    2,853

    Re: Do I need a variable speed pump?

    Actually 220 has two hot wires, one for each phase.

    Regarding the need or desirability of a VS pump over two speed or even single speed, a major consideration is the flexibility of a VS. I have a pool, spa and both have different flow requirements. Then there is the flow required by my SWG, and the solar heating system, oh yes, then there is the in-floor cleaning system. All these have their own speed/flow requirements and when more than one is used at a time, you can see that you may want many more than two speeds if you are trying to operate each at its best efficiency and function. Also the VS gives you the ability to program all your timing and speed changes right on the pump. Of course if you are using a sophisticated automation system, that could be a disadvantage or at least a bit of a challenge to integrate.

    If my VS pump didn't save me a dime, I would still love it just for the programmability and flexibility.
    chiefwej
    Tucson, AZ
    16x36 rectangular (19k) Pebble Tec play pool/spa, Pentair Intelliflo VS 011018, Super II 2hp (spa), Aqua Rite T-15 SWG, Pro Grid 60 DE, Hayward H400 & Heliocol Solar heating, A&A infloor system, fill water w/high CH and TA, 50 ppm borates,TF-100 test kit

  17. Back To Top    #17

    Join Date
    Dec 2014
    Location
    Sydney, Australia
    Posts
    43

    Re: Do I need a variable speed pump?

    One thing to be mindful of is will the low speed on your 2 speed keep your SW chlorinator full, I have a VS speed pump which would happily run at 800rpm but anything less than about 1200rpm the SWG cell housing wont stay full of water causing the low flow error and the whole thing shuts off...

    I don't see this being an issue anywhere on the forum though...
    --
    8M x 4M Inground Concrete, 40k Litres, Waterline Tiles/Quartzon, Viron P320 VS Pump, Sand Filter(Glass Media) Astral VX-9 SWCG, Heatpump w/ Solar Cover. Zodiac V3 4WD Robot. Bullfrog A8D Spa(1800Litres).
    --

  18. Back To Top    #18
    JoyfulNoise's Avatar
    Join Date
    May 2015
    Location
    Tucson, AZ
    Posts
    11,625

    Re: Do I need a variable speed pump?

    Quote Originally Posted by Dibbler View Post
    One thing to be mindful of is will the low speed on your 2 speed keep your SW chlorinator full, I have a VS speed pump which would happily run at 800rpm but anything less than about 1200rpm the SWG cell housing wont stay full of water causing the low flow error and the whole thing shuts off...

    I don't see this being an issue anywhere on the forum though...
    This is quite common in the sense that you can't always run everything at once. That's why many people opt for a VS pump and then use the scheduling and speed settings to run various functions - low speed for filtration, medium speeds for filtration and chlorine production & higher speeds to run solar heaters, in-floor cleaners and vacuum cleaners.

    But you are right, an improperly sized 2-speed pump could mean not generating enough flow for an SWG. Always check pumping curves before you buy if they are available. Or, better yet, ask here on TFP as we have many pump experts.


    Matt
    16k IG PebbleTec pool, 650gal spa, spillway and waterfall, 3HP IntelliFlo VS / 1.5HP WhisperFlo, Pentair QuadDE-100 filter, IC40 SWCG, MasterTemp 400k BTU/hr NG heater, KreepyKrauly suction-side cleaner Dolphin S300i robot, EasyTouch controls, city water, K-1001, K-2006 and K-1766 test kits, Mannitol test for borates

Posting Permissions

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