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Munchkin Humming Noise

CBennett
CBennett Member Posts: 5
in Gas Heating

We had pump replaced on Munchkin boiler and now whenever it fires up sounds like a cruise ship. Noise can be heard outside and 2 floors up. Boiler works fine but Noise throughout the day is unbearable

Comments

  • Alan (California Radiant) Forbes
    Alan (California Radiant) Forbes Member Posts: 4,243

    Is the new pump the same size as the old one? Is there a ball valve where you can adjust the flow to see if the sound changes or some way to turn off the pump for just a few seconds to see if it’s a flow issue? If not a flow issue, it could be combustion needing a combustion analyzer.

    8.33 lbs./gal. x 60 min./hr. x 20°ΔT = 10,000 BTU's/hour

    Two btu per sq ft for degree difference for a slab
  • CBennett
    CBennett Member Posts: 5

    The unit has 3 Grundfos pumps that have settings C1 low, C2 med & C3 Max. Just discovered that all 3 pumps were set at C3 max for a 2 story house. Not sure if contractor changed all the settings but was not making noise before he did work.

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  • CBennett
    CBennett Member Posts: 5

    All the same size, sorry didn't answer question. The one near gauge (closest to floor) ⁷was replaced.

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