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Water leaking

Geraldo Member Posts: 16
edited July 2016 in Oil Heating
Hi, I have an oil heat system and there is copper tubing on the back of the furnace that has a little flip handle on top that has a bucket placed under it and the bucket is full and leaking onto the cellar floor. What would cause water to be coming out of that?


  • 776v63
    776v63 Member Posts: 61
    Check the pressure gauge. What does it say? Is it a constant drip, or does water shoot out when the boiler runs?

    It's you pressure relief valve. It's job is to release pressure from the boiler if it gets too high. There are a few different things that can cause it to drip.

    Best bet is to have a professional come out.
  • Jamie Hall
    Jamie Hall Member Posts: 18,910
    776v63 said:

    Best bet is to have a professional come out.

    And fairly quickly. That is a safety device, and it is telling you that it isn't happy.

    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • Geraldo
    Geraldo Member Posts: 16
    Thanks, I would never try and fix it myself. Leave that to the professionals. I appreciate your comments. Just so you know a tech is on the way. The pressure looks to be 30, there was a new expansion tank put on about 6 months ago but I don't know if they replaced the pressure relief valve. It continues to come out like a stream of urine. Thanks again.

    I tried to edit the spelling earlier but hitting edit did nothing even though I tried 2 different browsers.
  • delta T
    delta T Member Posts: 870
    30 psi is too high, that is the pressure that the pressure relief valve is meant to open at, it is doing its job. This is typically caused by the expansion tank being water logged or not pressurized correctly, or not sized correctly. It can also be caused by a bad feeder valve that is leaking past and over pressurizing the boiler. Just because that expansion tank is new does not mean it was installed correctly. The pressure in the expansion tank must be checked and set with the tank DISCONNECTED from the system. It should be set to the desired fill pressure of the boiler (usually 12-15 psi for a normal residential system), and the feeder must be set to the same pressure.
  • Geraldo
    Geraldo Member Posts: 16
    Update. The tech was just here. One thing I forgot to mention was that the boiler feed line had big drops of water all around the cellar and even formed a small pool of water on top of the washer where the lines were overhead. You could also hear almost like air rushing when turning on the boiler feed line.

    The tech quickly diagnosed it as the tankless unit. He said it is filling up the block and then draining off. I asked if it was worth it or if I needed a whole new unit and he said everything seems in good shape so I could just replace the tankless unit.

    Previously I had oil companies providing support but I recntly went to a local company that delivers top quality heating oil at much better prices but they do not provide support. They gave me two names of companies they have built a relationship with and have had excellent results that are also reasonably priced.