pipes knocking

gidget

I HAVE A STEAM SYSTEM.    WHEN THE STEAM COMES UP IN THE A.M. THE PIPES START KNOCKING SO LOUD IT SOUNDS LIKE A CONSTRUCTION CREW IS WORKING.   ANY SUGGESTIONS  HOW TO STOP THIS FROM HAPPENING.

BobC

Setback?

How much of a setback is the system coming back from? steam systems don't respond well to deep setbacks.



What pressure is the system running at?



Bob

bobbyboiler

banging

Is this a new boiler?  if so, has the water line changed?

Jamie Hall

That banging...

is called water hammer, and it is caused by condensed steam (water) being in a pipe or pipes somewhere where it shouldn't be, and getting carried along by the steam until it hits a corner -- and when it hits that corner, it goes bang.



There are quite a large number of things which could cause this, so to try to zero in on it for you:



Is this a new problem?  If so, what was changed just before the problem started, like a new boiler or moving a radiator or rearranging some pipes in the basement?  That's always a good place to start looking.



If it's not a new problem, well... still, somewhere water is collecting it shouldn't.  It would help to know whether it is just at the beginning of a cycle -- just when the radiators are warming up -- or in the middle, or at the end, since the causes and cures for the various timings are different.



Whether it is a new problem or not, you might check the pressure the system cuts out at; if that is too high that could be part of the problem (that causes other problems, too, like spending too much money for fuel).



You should also look for any place where the steam pipes have sags in them, or can't drain back to the boiler in some way or other properly.



Is this one pipe steam (one pipe only to the radiator, with little vents on the radiators) or two pipe (self explanatory).  If it's one pipe, by the way, the radiator valves must be open all the way.  There are other ways to shut off a radiator if you don't want it to run.



Do take a look at some of the questions we've thrown at you and see what more you can tell us.  We'll get this.