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Thread: 2 pump systems

  1. Back To Top    #1

    Join Date
    Jul 2014
    Leesburg Florida

    2 pump systems

    I have a pool and spa. 1 pump is for the pool and 2nd is booster for spa. Everything feeds toward heater which has on one side from pool from spa. On the other side is to pool to spa coming from heater. Do I need to run both pumps at same time? When I try closing from pool and opening to spa with only spa pump running it does not seem to get enough water flow to turn on heater.

  2. Back To Top    #2
    JasonLion's Avatar
    Join Date
    May 2007
    Silver Spring, MD

    Re: 2 pump systems

    Welcome to TFP!

    When heating the spa you need the shared side of the plumbing set to spa only, on both the suction and return side. Normally the spa plumbing lines are fairly short and get better water flow than the pool side.

    I would start by checking that you are getting a strong return flow at the spa, best to try this with the spa jet pump off so it is obvious which return is coming from the heater. If not there is something blocking the flow, perhaps as simple as a full pump strainer basket or needing to clean/backwash the filter, perhaps something more complex.

    If you do have a nice strong flow, perhaps the heater is failing to sense the flow properly.

    Also, do you have a heater bypass? If so too much water might be flowing through the bypass.

    A photo of the equipment pad, and your filter pressure in both pool mode, and spa mode, will help us diagnose further.
    19K gal, vinyl, 1/2 HP WhisperFlo pump, 200 sqft cartridge filter, AutoPilot Digital SWG, Dolphin Dynamic cleaning robot
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