stages of heating cycle?

steamheatnewb

I am trying to troubleshoot a water hammer noise I am having at a pitched radiator with an old single pipe steam system. While reading many of the articles on this site, I see a reference to stages of the heating cycle - what is the meant by the "middle" or "end" of the heating cycle? Here is an example:



<ol><li>The steam quality is bad. It's not just faulty near-boiler piping

that can throw water up into the system. Dirty water, or water that has

a pH that's too high can do it as well. This type of water hammer

usually happens during the middle of the firing cycle.</li></ol>





Thanks!

Jamie Hall

Easiest way to look at this

is to see -- or more accurately, feel -- what is happening.  The early stage is when steam is first starting to be made, and is beginning to get out into the system.  It doesn't end with a definite mark, rather it ends for each radiator when the radiator is getting live steam -- that is, when the radiator, not just the pipe leading to it, is getting steam hot right at the inlet.  During this stage there is a lot of condensation going on in the steam mains and risers -- even in the best insulated system -- and if that condensation can't go somewhere, it bangs.



The middle stage, to my mind, is when steam is flowing to the radiators -- and, more important, the mains and risers are hot, so condensation in them is not a factor.  It is at that stage that water hammer from wet steam can become a real problem (it's there in the beginning stage, too, but masked by any condensate problems).



There are all sorts of problems which can cause wet steam; you have listed some of them.