South Dakota Open Loop Siphoning?

Discussion in 'Maintenance and Troubleshooting' started by samheidy, Mar 10, 2019.

  1. samheidy

    samheidy New Member

    Since install, I've had to keep upping the grains of hardness setting on my water softener and it still isn't the best. I figured the amount of water being used from the well now changed the makeup of the water...

    I attached a pic of some temp sensors I have been mounting to pipes to see if anything shows up.

    Green: Closest to DHW preheat tank, tank side of in line valve
    Yellow: 2nd closest, after green, 'cold' side of valve
    Blue: 3rd in line, after yellow, closest to cold water
    Red: Disregard, testing on one return loop of radiant floor

    Screenshot is with the valve open, desuperheater enabled. If I close the valve, the yellow and blue rise and stay at ambient with no water usage.

    Thoughts, questions?

    Attached Files:

  2. waterpirate

    waterpirate Well-Known Member Industry Professional Forum Leader

    Hi and welcome!
    Wells are living breathing things. Water usage will change the production of a well over time. Production changes in volume and quality are both common in the life of a well.
    Hope this helps
  3. samheidy

    samheidy New Member

    Thanks Eric!

    I understand wells change but to change the gallons to regeneration from 450 to 300 and still not very soft makes me wonder if it's 'stealing' from my softener. The temperatures stay at ambient with that valve closed so my thoughts are that either the desuperheater is forcing flow where it shouldn't be or geo main is 'siphoning' by flowing past my domestic main.

    I do not have a check valve between the softener and preheat desuperheater tank and the manual backs that up, but I question it..
  4. samheidy

    samheidy New Member

    Update: Open loop geo runs much less due to warmer temps and domestic water turned smooth as silk now. What is the proper way to keep it from 'stealing' from my softener?
  5. mtrentw

    mtrentw Active Member Industry Professional Forum Leader

    I'm not quite clear on what you mean by siphoning or stealing. I think your saying the system is up so that GEO system draws water before softener. DSH and thermal siphoning on the treated/soft domestic water side shouldn't cause increased use of water, just moving bits around that were already in the domestic loop. From your posts, it seems your softener system has some method to monitor flow (450 vs 300 gallons.) If that measure is accurate, the flow through is the flow through.

    Your discussion fits nicely with what Eric said, the well is a living object and changes based on demands. In your current lower demand regime, it's drawing water more gradually with less draw through the surrounding geologic formation. It would seem to me like the difference between gently flowing air through a filter and aggressively sucking air through the same filter. Which one will have more particles get through. Higher flows may also significantly alter the location where you are drawing water from. Whereas your traditional well use has pulled water through some defined 3d volume of earth, many of the minerals in that volume may have already been leached clear. Your larger draw regime may be pulling from further off virgin material more heavily loaded with free minerals.

    With a bit of knowledge and experience in farm soil management, I can tell you I am constantly required to add lime to my farm fields as rain leaches existing away to form clay layers several feet below surface. In heavy rain years, like I just experienced, that leaching and soil acidification becomes much more pronounced.
  6. samheidy

    samheidy New Member


    By stealing or siphoning I mean my main water line goes straight to the open loop, but my 'house' main or to be softened comes off with a tee within a foot of my pressure tank outlet (GEO keeps going straight.) This may be nothing but my thought would be a 'scavenging' effect while the mass quantity flows by.

    My softener does have a meter but I wouldn't consider any softeners meter 'revenue grade.' Even if it's flowing .1GPM but not detecting it, its 144GPD which is a ton of hard water diluting my softened water.

    If you look at my screenshot above with the temp sensors, it looks like hot water from my pre heat tank or desuperheater loop is flowing towards my softener (cold water supply.) If I shut the valve between sensors the heat spikes go away and stay ambient.
  7. mtrentw

    mtrentw Active Member Industry Professional Forum Leader

    I'd think at the T in your piping where geo water flows by the domestic takeoff, you'd likely get venturi type pressure differentials and some degree of localized mixing, but there wouldn't seem to be much room for significant volumetric draw on a closed system. Otherwise, it'd pull vacuum on house system. Is it possible the temperature following is simply a factor of heat condyction down the pipe?
  8. samheidy

    samheidy New Member

    I'd agree with the vacuum effect, I wasn't sure if crossover devices or anything would allow mixing?

    The temperature change can be seen in multiple locations between the pre heat tank and domestic inlet. I've had them on copper, pex, even before and after a water filter that is 'isolated' with plastic fittings. They all show the same trend as shown above and all show ambient with no activity during heat pump operation with either the domestic inlet or pre heat tank valve closed.

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