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Hot water from cold water tap

Roger Cowder
Roger Cowder Member Posts: 3
in THE MAIN WALL
Hi Everyone, last night I had a strange problem occur and wanted you thoughts. I have hot water comming out of the cold water taps and cold comming from the hot. Then it goes random and I only get warm from the hot tap. I closed the cold input and hot output valves on the HWH and oddly I got cold water from the hot taps. I thought that should stop all the flow going to the hot taps. I think this is because I have a faulty shower valve or something, am I right? I can't think of any other way for cold water to get to the hot side when I have the valves closed. How do I figure out which thing it is?
Thanks,
Roger

Comments

  • Matt Undy
    Matt Undy Member Posts: 256


    Is this only one faucet and is it a Moen?

    Matt
  • Roger Cowder
    Roger Cowder Member Posts: 3


    No, It happens all over the house. But the kitchen faucet is a Moen.
  • Chuck Shaw_2
    Chuck Shaw_2 Member Posts: 68
    make sure the

    valves supplying your washing machine are closed as well.

    Chuck
  • Ken_8
    Ken_8 Member Posts: 1,640
    If you closed the inlet and outlet piping to

    the water heater - and ANY water comes out of a hot water faucet - you have a cross connection - for sure!

    Now the only thing left to do is find out where.

    What did someone do that would create that condition?

    How about:

    1) All mixing valves/faucets that are suspect in a tub or shower?

    2) All single lever faucets?

    3) Washing Machine hose switch?

    4) A shower head stop being left closed while both faucets were left opened!

    I like # 4 the best. Now go close the shower valve(s) and open the shower head stop.

    Problem solved?

    To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"
  • John@Reliable_9
    John@Reliable_9 Member Posts: 122
    Had one early this year like yours.................

    and believe it or not turned out to be mixing valve inside the washing machine and not the shut-off. Odd thing was older washer with no parts so they had to buy a new washer to solve the problem.
  • lchmb
    lchmb Member Posts: 2,997
    another thought

    In some houses there is a mixing valve between the hot and cold that feed's your toilet. If this valve malfunction's it can also cause this problem...good luck
  • bob young
    bob young Member Posts: 2,177
    check valves

    swing check valves would have solved the problem. a simple code issue.
  • Larry Weingarten
    Larry Weingarten Member Posts: 3,599
    troubleshooting

    Hello: To find the source(s) of the problem, shut off the cold supply to the water heater and open a hot tap. It's best if the hot tap is not a single lever type. Then walk around the house and listen for running water sounds, particularly at that Moen shower. If you hear it from a sink, turn off either stop under that sink and see if the noise stops. Try turning off a stop at the clothes washer and listen for any change. You may need to shut off a stop at every other place just to prove to yourself that it's the shower. Try replacing the brass cartridge with the plastic, polysulfone one. It is designed specifically to prevent cross connection. I had one job where four cartridges leaked. Hot water at that house was really capricious!
  • EJW
    EJW Member Posts: 321
    Hot/Cold

    I have seen Moen single handles do this before, it can be mixing inside the faucet without even touching it. If you have a Moen have someone open another faucet in the house and feel the lines going to the Moen, if it is the culprit you'll know quick. If you have multiple Moens this could take some time.
  • Roger Cowder
    Roger Cowder Member Posts: 3
    Found it

    I checked all the things you guys recommended and it was my own mistake. In my garage I ran hot and cold (with shut offs) to my hose garden hose. Either my kids or my wife turned on both handles and caused the crossover. Thanks for the help, If anything like that ever happpens again I will know how to chase it down.

    Roger
  • Weezbo
    Weezbo Member Posts: 6,232
    :) as luck would have it :)

    i decieded to take a shower one day while near work in a house we had finished and hadnt sold yet...the cold water was HoT! and the hot water was hot then warm then cold ..:) was i ever lucky:) not only was i ten pounds lighter the next day i got a new cartridge and replaced it took another shower just to make sure:) Hurray! Alls well:)
  • EJW
    EJW Member Posts: 321
    Found it

    This happened to me in a building that didn't allow washmachines. They had one hooked up to the kitchen faucet and left both faucets turned on, It effected all 12 apts. Glad you found it..........sure your wife or kids left them on. EJW
  • John@Reliable_9
    John@Reliable_9 Member Posts: 122
    Bob, true check valve would've solved but.....................

    because machine valve was bad machine couldn't make hot or cold only warm so thats why it really needed to be replaced.
  • Robert O'Connor_7
    Robert O'Connor_7 Member Posts: 688
    Rodger...

    I'm glad that your cross connection problem has been identified. I'm concerned that you may have contaminated your domestic water supply though. You need backflow prevention out there. My recommendation is to install pressure type vaccuum breakers at each connection before you attempt to twin them together. Would you drink the water out of your garden hose? If you wash your car and leave the spray hose in the dirty/soapy water theres a good chance you might get the DUMP SWEATS pretty soon. True backflow prevention comes at a high price, like installing RPZ's @ the cross connection point but installing these inexpensive measures as I've suggested should take care of your problem..Robert O'Connor/NJ
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