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Noisy Hot Water System

We are visiting my MIL, and her Hot Water system is somewhat noisy.
This is zone 5 or 6, the boiler is in the basement.
It looks to me that the water heater is attached to the heating system. I have been coming here for years and never heard her or her late husband talk about the boiler heating the water.
The noise seems to be located in a loop that was added when the basement was originally finished. The piping is all copper with the noise that is associated with that. This is not that noise. This noise is a light banging not noise from copper pipes expanding and contracting.

In the picture you can see the device from Taco that is there to let the air out of the system. Seems like if this is mixed with the HW you will be constantly getting fresh water in the system.

No comments about the flexible tubing coming out of the WH. That was another relative.

Thanks in advance.


  • HomerJSmith
    HomerJSmith Member Posts: 2,441
    "It looks to me that the water heater is attached to the heating system."

    It really isn't. What is attached is the cold water supply to the water heater which is also connected to the cold water supply to the boiler, it's called the boiler feed. You would only be getting fresh water into the boiler sys if there was a massive leak in the boiler sys.

    You would need to show pictures of the zones that are making the banging sound.
  • hot_rod
    hot_rod Member Posts: 22,157
    Looks like a fairly new air vent on the scoop? Did someone work on it recently?
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • jmichelotti
    jmichelotti Member Posts: 2
    The basement had a flood and when they redid the walls they did some work so the baseboards fit the new interior walls.

    I don't know if anyone work on the boiler recently.

    What pictures of the zone do you need? For the zone I think is in question, the pipe rises from the back of the boiler and goes through the ceiling to the end of the basement and then back down. There are some valves where it turns.

    Thanks for straightening me out on the feed line. Nothing like competent help. I have a building with single pipe steam. I had a guy work on it for years who could keep it going. I found out after he died he was honest but not so good.

    I found two competent steam guys who essentially agreed on the problem solution. Replace the pressutrol with a vaporstat and create a clean out in the return before the Hartford Loop. That ended all the banging and many of the other problems I had over the years.