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    Mixing Valve Noise w/Video & Audio (17 Posts)

  • BigRob BigRob @ 4:40 PM
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    Mixing Valve Noise w/Video & Audio

    Has anyone heard a mixing valve make sounds like this before? This valve is a Watts MM430. Something is not right:
  • Steve Whitbeck Steve Whitbeck @ 7:25 PM
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    First off - WHY is your pressure so high. You have a problem that needs IMEDIATE attention.
    Is the noise a mechanical noise. Can You see the linkage?  Is the linkage moving when the noise happens?
  • Steve Whitbeck Steve Whitbeck @ 7:28 PM
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    We need more info and pictures of your boiler and near boiler piping.
  • Hydronicz Hydronicz @ 6:04 PM
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    Try to get a photo of the pipeing. Why do you guys think the pressure is high? That should be normal 50psi, its comming out of the coil, not the boiler pressure. Iv seen alot of holby valves making noises like that. If the temp fluctuates a lot id get a rebuild kit or replace it, if your temp is fine at 120 130 id leave it alone
  • Gordy Gordy @ 6:17 PM
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    Boiler pressure

    Should be 12 psi normally.

    Wondering what size relief valve? Why it's not popping off?
  • Hydronicz Hydronicz @ 5:59 PM
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    I think

    Your confused, the boiler pressure relief is most likely rated at 30lbs. His gauge is not reading boiler pressure its reading domestic water pressure, so if anything that shouls blow off the coil relief valve wich is prob set 100lbs or more.
  • Gordy Gordy @ 7:14 PM
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    Tempering valve

    Then it would be called. I was thrown by the tridictator gauge.
  • Zman Zman @ 6:19 PM
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    It is a dhw mixing valve. How is it piped? Is there a recirc pump?
  • Steve Whitbeck Steve Whitbeck @ 8:48 PM
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    On domestic water it is usually called a Tempering valve.
    On a boiler the same valve is a mixing valve - used to lower the boiler water temp down to a lower temp.
  • BigRob BigRob @ 12:44 AM
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    Hey guys, really sorry about the late response! Thank you for all your input. I didn't have the subscription enabled by mistake.

    The video is of the tempering valve output. The sound you hear is either the valve bouncing around or a water hammer. The tempering valve is pretty new. The previous setup had no problems whatsoever with water hammer, so I'm really stumped. The valve is a Watts LHMM433. The water hammer seems to be on the cold side only. Take a look at my pictures. I tried removing the integrated Watts integrated "flow checks" to no avail. Currently, the there is one swing check on the main water line from the city. The line them branches to two spring checks, one on the cold input to the mixer, the other to the hot water tank. The building is a 12 condo unit building with double occupancy and 2 full baths in each unit. The boiler room is on the top of the 3 story building. I've attached some pictures. Please let me know if you have any other questions. Thanks for your help!
  • icesailor icesailor @ 11:05 AM
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    I can't see everything there like the actual mixer, but something looks terribly wrong. There needs to be some sort of a potable water expansion tank AFTER the cold water check valve and the mixer. Is that Watts valve a true thermostatic mixer? Is that what is required in that jurisdiction?
    Mass. Code allows a small (1/8")  hole drilled into the check valve brass flapper to let some expanding water to get out and relieve pressure.
    If it is a Thermostatic Valve, is it sized properly. It is worse to oversize it than to grossly undersize it. Because I can't see or figure out where the valve is, the recirculating line usually goes into the thermostatic mixer.
    I hadone where the wrong valve "Watts N2" was spec'ed and installed. I put in a Leonard SM Series. It's hard to size thermostatic mixers. They work best when used fully and drop off with less usage. With no flow, you depend on the properly installed Recirc. line to keep the flow up and make it work. The one I fixed clanged every time a Solenoid Valve opened or closed in the kitchen or a hot water faucet was slammed shut.
  • icesailor icesailor @ 11:19 AM
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    Furthermore, I can't find a Watts LHMM 433 listed with them, Watts.
    They also have this warning on all their thermostatic valves.
    When I had the problem with the N2 Mixer in a nursing home, I called watts and a woman engineer ripped my head off and told me to get it out of there IMMEDIATELY because is wasn't designed and approved for that application. Symmons didn't have a valve. Only Leonard and Powers had them. Maybe more now. And maybe Watts bought out someone with the proper. listed valve.
    Watts Hot Water Master Tempering Valves cannot be used for
    tempering water temperature at fixtures. Severe bodily injury (i.e.,
    scalding or chilling) and/or death may result depending upon system
    water pressure changes and/or supply water temperature changes.
    ASSE standard 1016, 1069 or 1070 listed devices such as Watts
    Series MMV, LFMMV, USG, LFUSG, L111 or LFL111 valves should be
    used at fixtures to prevent possible injury.

    The Watts Hot Water Tempering Valves are designed to be installed at
    or near the boiler or water heater. They are not designed to compensate
    for system pressure fluctuations and should not be used where ASSE
    standard 1016, 1069 or 1070 devices are required. These Watts valves
    should never be used to provide “anti-scald” or “anti-chill” service.

    Need for Periodic Inspection: Periodic inspection by a licensed
    contractor is recommended. Corrosive water conditions, temperatures
    over 210°F, unauthorized adjustments or repair could render
    the valve ineffective for service intended. Regular checking and
    cleaning of the valves internal components and checkstops helps
    to assure maximum life and proper product function. Frequency of
    cleaning depends upon local water conditions.


    You are required to thoroughly read all installation instructions and
    product safety information before beginning the installation of this product.

    INJURY AND/OR DEATH. Watts is not responsible for damages resulting
    from improper installation and/or maintenance.
    Local building or plumbing codes may require modifications to the
    information provided. You are required to consult the local building and
    plumbing codes prior to installation. If this information is not consistent
    with local building or plumbing codes, the local codes should be followed.
    Watts is not responsible for damages resulting
    from improper installation and/or maintenance.
    Local building or plumbing codes may require modifications to the
    information provided. You are required to consult the local building and
    plumbing codes prior to installation. If this information is not consistent
    with local building or plumbing codes, the local codes should be followed.

  • Zman Zman @ 10:56 AM
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    When does the noise occur? Does it go away if you turn off the recirc pump?
  • Zman Zman @ 11:18 AM
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    It looks likes you have an abundance of check valves and where is the expansion tank?
    Are both of the valves returning from the recirc pump open? It needs to have free flow to either the hot or cold side of the mixer.
    It looks like the tempering valve is laying on it's back in the middle of the picture, directly below the gauge.
  • Zman Zman @ 11:32 AM
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    Oh my!

    This is the valve he has
    Everything is going to be OK.
  • BigRob BigRob @ 2:03 PM
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    Thanks guys

    Hey guys, thanks for your input and caution. There is an expansion tank between the tank and tank check valve. You can see it in the top left of the first picture. The recirculation lines from the pump to the cold tempering valve input and tank have valves and they are open and set to maintain the recirc loop temperature.

    My current thoughts:

    1. I'm wondering if the recirculation line temperature is fluctuating and causing some volume and pressure changes which are not immediately absorbed by the expansion tank.
    2. I wonder if air is collecting in the high cold inlet pipe and high hot outlet pipes. The reason I say this is that while I was turning down the tempering temperature I hear a bunch of air bubbles pass through as the cold water flow increased. The cold inlet and hot outlet are literally the high point of the system. I think I'll try this again and see if I hear anything. If the tempering valve is oversized, perhaps I'm not getting much flow to carry air out.
    3. Maybe some crap is gumming up the tempering valve internal components

    Sorry if I missed any questions- quick reply during work. Will reread later.
  • BigRob BigRob @ 12:33 AM
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    Hello all, I called the factory and they told me where the model number was located. It was on top of the valve and it was hard to see with the valve mounted so high. The tempering valve is a LHMM434-1 and Powers recommends the LHMM431-1.

    I came up with 113 fixture units for our building. 7 units have 2 full baths with tubs w/overhead showers. Five units have 2.5 baths with tubs w/overhead showers. All 12 units have dishwashers and laundry. 113 fixtures units is around 33-38gpm based on some stuff I found online. Using the powers web tool with the apartment/multifamily option and adding 12 laundry units I get 29gpm.

    Powers says when a valve is oversized the actuator can go bad in about 6 months to a year. It seems that is the case.

    I'm considering putting two Honeywell AMX102-UT-1LF's in parallel. Thoughts? Should I reverse return them or stage them?
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