"Water Flow" status light - WaterFurnace Premier AT

Discussion in 'Maintenance and Troubleshooting' started by go2africa, Jan 26, 2014.

  1. go2africa

    go2africa New Member


    First post to GeoExchange. It has been a Great source of info. Thanks.

    During the recent Midwest cold spell my PremierAT unit shows the "Water Flow" fault every 24 hours. I reset the unit (Power off/on) and the unit will run for another 24-36 hours. The AUX light on the thermostat does not come on when the unit shows the "Water Flow" fault. Does this mean the unit is not using the Aux Heat and continues to use the geo source?

    The unit is +18 years old. The previous owner says he had water flow issues in the early days due to incorrect installation of the ground loop (once the loop enters the basement it has a couple of 90 degree turns going up/down internal walls to the actual unit). Apparently a different WF approved installer had to use an extra large pump to remove any air pockets. The problem was solved for several years.

    Upon investigating we see there's a direct water line plumbed into the ground loop using a pressure and one-way valve. I assume this is used to continuously keep pressure in the loop over the years. My concern is if the anti-freeze is becoming diluted with this miniscule filling over time.

    What are my next steps?

    Last edited by a moderator: Jan 26, 2014
  2. urthbuoy

    urthbuoy Well-Known Member Industry Professional Forum Leader

    Go2africa (I will be going this Spring),

    Get your pressure drop across the unit. Tells us whether their is pressure in your ground loop and the flow. If you have no way of doing that, is the pump noisy with air? A pressurized system without air in it, is generally quite quiet.
  3. go2africa

    go2africa New Member

    Hi Chris,

    The pumps are quiet - extremely quiet.
    My friend is bringing gauges today.
    I'll revert with pressure readings and hopefully temperatures across the system.
  4. go2africa

    go2africa New Member

    Hi Chris

    Ok. Pressure readings follow:
    * From the Loop - 51 psi (inlet to geo unit)
    * To the Loop - 48 psi (outlet from geo unit)

    My heating and cooling mate (experience with Bryant geothermal units) says the pressure is Ok. Is this correct?

    I'm unsure how to get an accurate temperature reading on the loop. Any guidance?

    The unit has been stable (no "water flow" warning lights) over the last cold spell - last 3 days. I did have the thermostat set on 68. This morning I set thermostat to 69 and within 15 minutes the "water flow" light came on.

    I have 2 geothermal units in the house. The main unit is a 5 ton unit. The 2nd unit (upstairs) is smaller. I have over 4000' of pipe installed - 2 separate loops.

    What's the next step?
    * Has the record winter freeze caused the unit to exhaust all remaining heat reserves from the ground loop?
    * Could there possibly be an internal issue with the "water flow" warning system?


  5. Mark Custis

    Mark Custis Not soon. Industry Professional Forum Leader


    You may have answered your own question. Air in a system can halt flow better than a ball valve.

    I doubt that you used up all the heat.

    Most times the water flow sensor uses temperature to judge the water flow. You could test the sensor against a good thermometer to eliminate the sensor from the mix.

    BTW as you move through this only change one thing at a time.

  6. go2africa

    go2africa New Member

    Hi Mark


    Are the pressure levels correct?

    I'm getting strap-on temp gauges over next couple of days.

    How do you check anti-freeze levels?

    My loop has a one-way valve and pressure valve attached directly to our water line. Unsure if over time the anti-freeze mixture hasn't been diluted.

  7. Mark Custis

    Mark Custis Not soon. Industry Professional Forum Leader


    I do very weird stuff compared to the GEO Pros of old. I do not use flow centers, with push pull pumping. I do not live and die with renolds numbers. I have never installed Pete's Ports in a system, as a means of testing delta T and delta P. I do not care if the loops are made of pex using CTS, (copper tube size) or HDPE srd 11 using IPS, (iron pipe size).

    I like doing the math.

    I went back to school to get a PE. The education counselor told me to take remedial algebra, since I had not taken any college level math for more than twenty years. So I did. With the employer educational reimbursement program in hand , I put the class and the books on my credit card. I brought home the book and upon opening the pages, I found out it looked to me like Chinese from the first page past the forward.

    I was very down when my then fifth grade daughter was able to translate the Chinese to Dad speak. I was working for a major Cleveland Ohio player at the time and worked with the service manager and the dispatcher to be able to attend the classes on time. All went well until a cold event like the last two caused me to miss the final exam and I failed the course.

    I made my own choice.

    I got heat to a twenty suite apartment building in a ghetto and missed the exam. Fuel gas companies have their rules.

    I was then able to see that I can learn with out spending money or time.

    If your system is piped with an auto fill plan, I would guess there is a leak.

    I pipe that way but turn the incoming water valve off. Since I use expansion tanks, air eliminators and such, and live pressure gauges and thermometers it is easy to spot changes.

    I run my systems at around 12# PSIG. If the air is out that is all that one needs.

    If you wish to test what you have in the loops you need to drain enough fluid to float a hygrometer.

    My guess is if there is a make-up water system on your loops it was added rather than find and fix the leak.

  8. urthbuoy

    urthbuoy Well-Known Member Industry Professional Forum Leader

  9. Mark Custis

    Mark Custis Not soon. Industry Professional Forum Leader

  10. go2africa

    go2africa New Member

    Thanks, Mark.

    I'll discuss with my HVAC mate and decide way forward. I don't think he has a pumping station.
    I think we'll first try to inject some anti-freeze into the system.
    I don't think turning up the water line inlet pressure valve will do anything as the air has nowhere to go.
    Is an expansion tank difficult to install?
    Is there a special anti-freeze I need to use? Can you mix types (I have no idea what solution is currently in the system)?

  11. AMI Contracting

    AMI Contracting A nice Van Morrison song Industry Professional Forum Leader

    you do not want to mix refrigerants. how hard a tank is to install depends on the current plumbing and access. Climatemaster puts tanks in their systems now to counteract seasonal pressure changes.
  12. Mark Custis

    Mark Custis Not soon. Industry Professional Forum Leader


    I think you meant antifreeze solutions rather than refrigerants. I do not think one should mix either.

    Last unit we installed was a Bosch. So Climate Master is now including installation of expansion tanks in their directions? Can air eliminators and single pumps be far behind?

  13. AMI Contracting

    AMI Contracting A nice Van Morrison song Industry Professional Forum Leader

    Yes Mark I meant antifreeze but share your advice not to mix either. The CM units with onboard flow centers also have onboard pressure tanks.
  14. go2africa

    go2africa New Member

    Hello and thanks everyone for the input.

    * We borrowed a pumping unit on Friday evening. We hooked up to loop and ran for 3 hours. We also mixed in our antifreeze solution at the end.
    * We then fired up the geo unit and let run for the night with the outside supply line shut off. We lost water pressure from 32 psi at start (after disconnecting pump Friday night) to 12 psi Saturday morning. It was steady between 12-19 psi during the day on Saturday.
    * Saturday night we reconnected the pumping station to mix the last of our antifreeze. We then disconnected and left the geo unit to operate for the evening. We're now between 12-19 psi up to noon today (Sunday 2/2/14).
    * The unit hasn't had a "Water Flow" error since Friday morning.
    * HOWEVER - I now have a Grundfos 26-99F pump running extremely hot and pulling twice the amps as the other unit. Likely a bearing has gone. I've ordered a new one off Amazon.

    My obvious concern now is the drop in psi. If it continues I likely have a leak in the loop. Unsure if there is anyway to easily (and cost effectively) find a leak in 400o0' of 1"1/2 pipe 8'-10' underground. We'll start search my looking at the connections inside the house. Any advice here will be greatly appreciated.

  15. AMI Contracting

    AMI Contracting A nice Van Morrison song Industry Professional Forum Leader

    I have not tried loop conditioner, but some here have had success with it. Also non-pressurized flow centers often remedy leaks.
  16. mtrentw

    mtrentw Active Member Industry Professional Forum Leader

  17. go2africa

    go2africa New Member

    Thank you.

    Replace my pump motor with another used motor my HVAC mate had.
    My unit has run intermittently for 7-10 hours at a time between manual resets (power off/on) but continues to shut down with the "water flow" indication.
    I can recharge / pressurize the ground loop to 50 psi via the installed direct water supply connection.
    Latest readings (I now have a digital thermometer...)
    To Loop : 43 psi / 34.9F
    From Loop: 48 psi / 32.2F
    It's pretty clear there's a leak in ground loop.
    I've ordered 2 x 8oz bottles of Geoloop leak seal. I'd like to try this before deciding to replace ground loop.
    - Can I add this through the p/t port and pressurize to 50 psi and let pumps run for 24 hours OR use a Flush Cart?
    - is the above pressure drop within limits?
    - is the above temp drop showing decent efficiency?



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