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Hot water recirc

Good morning. My name is Ross Terrano and I am the owner of Terrano Plumbing & Remodeling here in South Florida. I have a project that we have a situation on a hot water re circulating system. The Condo is finished and it seems after discussing the project with my lead mechanic, somehow the return line was never completed in a loop. It seems that instead of looping the hot water to each fixture and return to the circulator they ran a dedicated return line and branch off to the existing hot water line in each fixture group. The problem right now is we have no cold water to the fixtures. The hot water is crossing over to cold water.

Please see attached drawing of what I believe is going on. If you can call me on my cell or e-mail me back I would really appreciate it. I am trying to make this work without opening holes throughout this finished Condo.


  • Abracadabra
    Abracadabra Member Posts: 1,948
    Sounds like someone tied a return into the cold. Is the cold out of the hot water heater hot?
  • SWEI
    SWEI Member Posts: 7,356
    Does the circ have a check valve?
  • Zman
    Zman Member Posts: 7,573
    I agree with SWEI. A missing check valve or a cross connect at a fixture.
    "If you can't explain it simply, you don't understand it well enough"
    Albert Einstein
  • icesailor
    icesailor Member Posts: 7,265
    I don't think that it is installed as per your drawing. Is a pump installed and is it running? There's missing lines.

    Do you want someone to cast an eye upon it?
  • Larry Weingarten
    Larry Weingarten Member Posts: 3,336
    Hello: I'd start with a test for cross connection, which is just turn off water to the heater and open a hot tap. It should run only a few seconds. If it keeps running, cold is finding it's way into the hot side. If you find no cross connection, consider using a demand pumping system like www.gothotwater.com.

    Yours, Larry
  • Jack
    Jack Member Posts: 1,047
    Rossterrano, I'd say yes to Ice!
  • RobG
    RobG Member Posts: 1,850
    If Icesailor (who is now retired and living in Florida) is offering to come out and have a look I would take him up on the offer.
  • jonny88
    jonny88 Member Posts: 1,139
    agree with swei look for check valve,we once had a problem with a defective cartridge in a shower body ,found the culprit on the 11th floor and was causing a lot of issues with the risers.
  • icesailor
    icesailor Member Posts: 7,265
    First, look at the check stops and be sure that they are closed on any and all thermostatic mixing valves. Make sure that ALL Single lever shower valves are OFF. Especially if they have any positive shut off devices on the shower heads.

    I think he found his problem though. Not another word.
  • Roohollah
    Roohollah Member Posts: 135
    Dear Colleague ,

    It may also the problem cause by automatic hand spray of faucets in bathroom or the facilities .For instance, A single lever faucet with automatic hand spray (which works whenever the user presses the button ) can lead the hot water into cold line or viceversa .In other words , the lever of the faucet is pulled out and the water from both sides of the faucet should enters the one whose static pressure decreases due to an open faucet in system .

    I appreciate you all for sharing practical views ,