Become a TFP Supporter Pool Math Forum Rules Pool School
Results 1 to 8 of 8

Thread: MinimaxNT wont work with new vari speed pump

  1. Back To Top    #1

    MinimaxNT wont work with new vari speed pump

    I have installed a Hayward Variable speed Eco Star pump. Since my installation, I have had a problem getting the MinimaxNT heater to run. The local gas repair person has installed a new pressure switch, which temporarily solved the problem. The heater starts up, and runs until the vari speed stops to adjust its programmed speed. At this time, the heater shuts down and will not restart, unless the pressure switch is "jumped". I am wondering if anyone has had experience with lower flow heater issues due to vari speed pumps? The pool next door has the identical pump, with no heater issues, even at very low RPM.

    Any suggestions would be appreciated.

    Thank you

  2. Back To Top    #2
    Mod Squad Bama Rambler's Avatar
    Join Date
    Jun 2009
    Location
    SouthWest Alabama
    Posts
    22,333

    Re: MinimaxNT wont work with new vari speed pump

    A few of quick questions and maybe we can help.
    Does the pump actually stop then go to the programmed speed, or does it just go from one speed to the next?
    Do you have to physically "jumper" the switch to get the heater to restart?
    What is your filter pressure at the start and porgrammed speeds?
    Dave J. TFP Moderator
    24' x 52" Round AGP. 2hp/¼hp SPL Power-Flo 2-speed pump. 200sqft Waterway Cartridge Filter. 45MHP2(3GPD) Stenner Peristaltic Pump
    Pool School ----- Pool Math ----- TF-Test Kit

  3. Back To Top    #3

    Re: MinimaxNT wont work with new vari speed pump

    Thank you for the reply.
    The pumps stops very briefly, then starts up on the next programmed speed. I currently have the pump set up so that the RPM is not less than 1750. I am jockeying back and forth between 1750 and 2850, just until I can figure the heater out.

    The filter is a Cartridge, and the pressure runs between 15-25 psi depending on the RPM.

    I also trimmed the return valves back a touch, to ensure that I had enough pressure for the heater on one occasion as part of my troubleshooting.

    The pressure switch has to be physically jumped, even at the higher RPM setting. Once I have it running, I can turn the heater on and off using the temperature feature or toggle switch.As soon as there is a stoppage in flow, or if the hydro is turned off at the breaker panel, I have to jump the switch to restart.

    Everything seems to point to the pressure switch, even though it was just replaced. Do you suppose the heater issue is totally a heater problem, and just a coincidence that I have a new vari speed pump?

    Thank you
    Rick

  4. Back To Top    #4
    Mod Squad Bama Rambler's Avatar
    Join Date
    Jun 2009
    Location
    SouthWest Alabama
    Posts
    22,333

    Re: MinimaxNT wont work with new vari speed pump

    I think it's strictly a heater problem. I thought the variable speed pumps went straight from one speed to the next without a pause in between. Maybe not. If it stops completely that would stop the heater and since your having to jump the switch to get it to start back.
    I think the problem is in the board in the heater.
    Dave J. TFP Moderator
    24' x 52" Round AGP. 2hp/¼hp SPL Power-Flo 2-speed pump. 200sqft Waterway Cartridge Filter. 45MHP2(3GPD) Stenner Peristaltic Pump
    Pool School ----- Pool Math ----- TF-Test Kit

  5. Back To Top    #5

    In the Industry

    Join Date
    Mar 2011
    Posts
    441

    Re: MinimaxNT wont work with new vari speed pump

    Some may pause, or stair step between speeds.

    A heater pressure switch only needs 1-3 psi to activate so unless you filters are really dirty, you shouldnt have any issues closing the pressure switch. It sounds to me like you need a new pressure switch.
    20X40 30,000 gallon gunite pool

  6. Back To Top    #6
    bobodaclown's Avatar
    Join Date
    Apr 2011
    Location
    Lakeland, FL
    Posts
    2,351

    Re: MinimaxNT wont work with new vari speed pump

    On your model is there a lock out (timer) feature that makes sure the system doesn't restart right away to ensure built up gasses have a chance to dissipate?
    17K Kidney Shaped Pool Concrete (Diamond Bright) Pool, 3/4 hp 2 speed 115V Sta-rite Duraglas PEA5D-180L/P2R5D-181L (Impeller C105-92PS Diffuser C1-216P), 1.5 piping, Pentair CC100 Filter , Heat Siphon 100K BTU Heat Pump Pool Heater, Flow meter Blue White Flowmeter Model No. F-30150P, Hayward Astrolight SP0581N, SWCG CalimarTitanium Edition TE45 , Dolphin Nautilus Plus with CleverClean, Lakeland Florida

  7. Back To Top    #7

    In the Industry

    Join Date
    Mar 2011
    Posts
    441

    Re: MinimaxNT wont work with new vari speed pump

    Quote Originally Posted by bobodaclown
    On your model is there a lock out (timer) feature that makes sure the system doesn't restart right away to ensure built up gasses have a chance to dissipate?
    Nope, not on any pool heater I have touched.
    20X40 30,000 gallon gunite pool

  8. Back To Top    #8

    In the Industry

    ps0303's Avatar
    Join Date
    Jul 2011
    Location
    FL
    Posts
    3,435

    Re: MinimaxNT wont work with new vari speed pump

    If you jump the pressure switch and it works fine, then it's the switch.
    Paul
    http://www.gastekservices.com A word of caution: When working with gas and electrical you might want to consider a licensed contractor. Consider the value of your life and others around you. If you would like to provide a review of the help I provided, please use the following link to leave a review. gastek - Google Search,

Posting Permissions

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