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Hot Water Recirculator Comfort Valves and Sensor Valves

Steverino Member Posts: 140

above is a link to Grundfos' website for your pump. Check out page #5 & #6. The problem may be with the valve located below your sink, or perhaps the timer located at your water heater might not be set properly.


  • Kurtis
    Kurtis Member Posts: 1
    Hot Water Recirculator Comfort Valves and Sensor Valves

    I have a Grundfos comfort series hot water recirculation system similar to the Watts Premiere instant hot water system installed in my single story home. The pump is connected to my homes hot water heater. Before we had the system installed we always had cold water available from our cold water faucets. Since installing our Grundfos comfort series recirculator we only get room temperature water from our cold water faucets. As a test, I unplugged the power to the pump for a couple of days so it wouldn't recirculate. But, for some reason, our cold water remains at room temperature instead of cold like it was before we got the system. Could the comfort valves some how be causing the loss of our homes cold water even with the pump unplugged?
  • JackEnnisMartin
    JackEnnisMartin Member Posts: 70
    Recirculation hot water system

    May I suggest, just off the top of my head ,that somewhere in your home the hot and cold water connections are communicating with each other? The systems have only just resulted ;so ,I can only think the installer has { innocently I am sure } cross connected the lines or something is holding a seat open slightly allowing the hot and cold water lines to cross connect. I would suggest you try and shut off all the lines going from your hot water source to the house manually and then check your water tempreature after say a half hour to allow thermal cool down of the pipig so you do not get a false reading in temperature. If the cold water is now cold you have the answer to your problem.

    Good luck and all the best

    Jack Ennis Martin
  • Had almost the same situation

    with a Grundfos I installed in my sister's home . There would be a momentary spike of very hot water when you opened it fully in the cold position . Keeping it running would only produce lukewarm water on the cold side . I never found out if it was a defect in the piece that connects under the sink . I ran a small diameter pex pipe back to the heater to make it a dedicated recirc line . Works fantastic .
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