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Expansion noise in baseboard on slab

Tom_26 Member Posts: 5
Have new install with two zones and boiler-mate on Munckin boiler. The first zone of loop has expansion noise when let to cool down at night, very slight noise during the day. The loop is a reverse loop on slab with 80lf with equal return element lenght 35ft. Boiler max temp of 190. The section that is noisy is by front door but that lop runs through bedroom.

Have ordered thermal expansion coupling for that loop but had to be ordered.
Any suggestions?


  • Tom M.
    Tom M. Member Posts: 237
    some things to check

    Check that the return pipe is not resting on the element or touching the housing or support brackets. Check that the element doesn't have any bent or rotated fins that may be contacting the housing. Check that the nylon sliders are properly installed and that the element moves freely. A long run of copper will really need to move as it expands. Hope this helps.

    Tom M.
  • Big Ed
    Big Ed Member Posts: 1,117

    With a da-da-Da-DA noise,Look where the pipe is rubbing against wood and loosen it up or place a rag between as so the pipe can slide...Check where it comes up through a wood floor or through a wall..... Heating pipe + Wood = Noise

    With ting-ting-ting noise check for the fins of the base board sitting bare on it's rack with out it's slide...
  • hr
    hr Member Posts: 6,106
    I'm not clear

    are the pipes to the baseboard run in, or below, a concrete slab? If so they should be insulated where they come through the slab. Hopefully they are insulated all the way to the boiler :)

    If they do poke through the slab you may not have enough room for expansion movement.

    The expansion couplings will make a difference, if this is the case.

    Any way to use a reset control and possibly lower that 190 temperature? Minimizing the temperature swings, or getting close to constant circulation with reset control, will greatly effect the expansion movement and noise.

    hot rod

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  • Mark Eatherton1
    Mark Eatherton1 Member Posts: 2,542

    Doo doooo doo, a dah dah DAH, a ting ting ting, an' all I wanna to do is to comfort you...

    Was that Sting???

This discussion has been closed.