# Steam pipes generating banging noise



## Dezso3 (Aug 30, 2009)

I have a steam heating system, and we just had a brand new boiler installed not too long ago. Right after it was installed, the pipes began generating a very loud banging noise (water hammer), so we called the contractor who installed the boiler, and he "flushed out the system," which made the very loud banging go away. However, although the pipes do not bang as loudly as they used to, it is still noticeable. Lately what I have discovered is that the pattern of banging is completely random. There is no telling when the pipes will make noise. Sometimes when the heat turns on one of the pipes leading to a radiator in the living room will make on large "bang!" and then be silent for the rest of the heating cycle, and sometimes when the heat turns on that same pipe won't make any noise. As I said earlier, it's completely random. Every single day I wake up at around 5:30 in the morning when the heat goes on, and cannot fall back asleep until school starts at 7. So if I go to bed at 11, then instead of sleeping 8 hours like I should, I only sleep 6 1/2







If I weren't so sensitive to noises while asleep then it wouldn't be a problem in the first place. A contractor said he can redo the pipework so that the pipes are pitched properly for $1800, but my dad doesn't want to pay such a large sum of money. Any suggestions as to what I should do?


----------



## spark plug (May 5, 2009)

Dezso (read De-Jeux. Origin. Hungarian) 3. (Poster #1)
The banging in the pipes, definitely is a result of pitch (Angle). If they are not pitched at the right angle, water from steam that has cooled remains in the system instead of falling back to the boiler. When the pipes heat up again, the (cold) water, now turning hot is trying to expand very rapidly. the only remedy is to redo the pitch of some of the pipes, so that the cooled steam can return to the starting point.:yes:!


----------



## Renovator2209 (Jan 15, 2010)

I had a similar problem that was caused by air getting into the steam pipe lines. Also, I had a radiator valve that was slightly open and a crack in one of the steam pipe lines underneath the house. I would hear two banging noises in the middle of the night. Finally, it went away after one heating season.


----------



## NHMaster (Dec 21, 2009)

Hammer is caused by water flashing back into steam in the piping. Usually caused by the following.

1 - return pipe or pipes are partially plugged.

2 - Radiator traps are not working

3 - Main line F&T' s not working

4 - Pressure trol set too high

5 - condensate return pump ( if applicable) not working or the vent is plugged.

6 - Improper pitch on return pipes 

If it's a new boiler the chances are that it is because the installation has loosened years of mud and rust in the pipes and you now have some clogged piping and or the new boiler makes steam a lot faster than the old one so the pressure needs to be adjusted as well as the differential.


----------



## AllanJ (Nov 24, 2007)

In some but not all cases the pitch of the pipes can be corrected by setting radiators up on small wooden blocks. The key to the success of this method is some give to the steam pipes under the floor, namely not passing through one stud after another via holes barely large enough.

In "one pipe" steam systems there is enough room in the pipes for steam to go up and water (condensed from the steam; called condensate) to go back down. But if water collects here and there due to pitch changed for the worse as the house settled then there isn't enough room and water hammer results.


----------



## spark plug (May 5, 2009)

AllanJ said:


> In some but not all cases the pitch of the pipes can be corrected by setting radiators up on small wooden blocks. The key to the success of this method is some give to the steam pipes under the floor, namely not passing through one stud after another via holes barely large enough.
> 
> In "one pipe" steam systems there is enough room in the pipes for steam to go up and water (condensed from the steam; called condensate) to go back down. But if water collects here and there due to pitch changed for the worse as the house settled then there isn't enough room and water hammer results.


Putting one side of the radiator (tilting) up on small pieces of wood as a remedy for "Water Hammer", near or in the radiators is possible because the Union past the valve is flexible. (It has some play)!


----------



## Leah Frances (Jan 13, 2008)

go to www.heatinghelp.com and start reading could be that your new install caused some problems.


----------



## Giianee (Feb 20, 2010)

How sure are you that the new boiler sized properly? 
Is this a one pipe or two pipe system?
Is there an equalizer pipe?
Did the contractor rebuild the wet return?


----------

